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Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated

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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 27 Aug 2017, 12:00
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kablayi

According to OG explanation to a similar problem (OG2017, problem 723), comma ing modifier must have distinct object to refer.

Emily Dickinson’s letters to Susan Huntington Dickinson were written over a period beginning a few years before Susan’s marriage to Emily’s brother and ending shortly before Emily’s death in 1886, outnumbering her letters to anyone else.

I don't understand why in this example "outnumbering" does not have a distinct object to refer to but "..., making the sloth" is considered to have a clear referent, which is "fossils"

The Dickinson letters case has a deep meaning issue. The crux of the matter is that the letters outnumbered the letters she wrote to anyone else. The out number factor has to be expressed in a finite rather than expressed as an additional info. That is the reason A is rejected but E is preferred.
However, the sloth case is very different. Herein 'making' does modify the fossils and their standing testimony to the ancientness (it is better to call it a subject and its action rather than an object)
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 31 Oct 2017, 01:02
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souvik101990 wrote:

Verbal Question of The Day: Day 146: Sentence Correction


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Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

B. sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on

C. sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of

D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

Every question of the day will be followed by an expert reply by GMATNinja in 12-15 hours. Stay tuned! Post your answers and explanations to earn kudos.



Option A :
Verb tense : "made" is incorrect as the fact still stands true.
Construction : "comma + and" requires an Independent clause. However, "dated" has no subject

Doubt: Which of the following construction is correct:
Subject Verb1 ,and Verb2
Subject Verb1 and Verb2


Option B:
Pronoun : "they" has no clear antecedent
Subject Verb : Fossils (plu) and "has been dated" (singular)

Option C:
Subject Verb : Fossils (plu) and "was dated" (singular)
Pronoun : "this" has no clear antecedent

Option D:
Subject Verb : Fossils (plu) and "have been dated" (plu)
Construction : Verb+ing form states the result of the finding and has the same subject as that of modified clause
Pronoun : Replaces "this" with "the sloth"

Option E:
Subject Verb : Fossils (plu) and "was dated" (singular)
Verb tense : "made" is incorrect as the fact still stands true.

Answer : D
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 31 Oct 2017, 13:42
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Hello fmik7894

You have presented a good analysis of this rather confusing official sentence. Great job there. :thumbup:

I will be glad to help you out with your query. :-)


Quote:
Doubt: Which of the following construction is correct:
Subject Verb1 ,and Verb2
Subject Verb1 and Verb2



Out of the two structures, the second structure is ideal because the connector is not followed by a comma when it joins only two entities in a parallel list.

Having said that, I would like to add that the first structure is not incorrect. There can be a comma before the connector even if it joins only two elements in the parallel list.

We see such structure when the parallel elements are pretty long. So the comma before the connector presents a necessary pause to help understand the meaning of the sentence better.


Quote:
Option A :
Construction : "comma + and" requires an Independent clause. However, "dated" has no subject



Please note that dated is NOT a verb in this official sentence. It is a verb-ed modifier like found. Since found and dated has been used as noun modifiers in this sentence, they form a parallel list and hence, we see dated preceded by and.


Hope this helps. :-)
Thanks.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 31 Oct 2017, 14:06
aceGMAT21 wrote:
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

Analysing the original sentence,

1. FOUND can be a VERB or a VERB-ED modifier. As sloth is present next to found, it seems "found" is the verb for sloth. But, sloth cannot do this action of finding. Thus, found is not the verb for sloth. Similarly, found is not even the verb for arms as well as fossils.

2. Found as a VERB-ed MODIFIER can modify any of these 3 : fossils; arm; sloth. But the portion after "and", dated clears this confusion. As dated cannot modify sloth or arm.

3. The COMMA before AND is not making sense. Since its only a list of two items. For a list of more than two items, we place a COMMA before AND.

4. The pronoun "it" is ambiguous. As it can refer to the arm as well as the sloth.

A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
INCORRECT for the reasons mentioned above.

B. sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on
"They" refers to whom?? ALso, Has been dated indicates the PRONOUN NUMBER AGREEMENT ERROR as the SUBJECT fossils is plural. The pronoun "it" can refer to the sloth as well as the arm. Therefore, INCORRECT.

C. sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of
The usage of relative pronoun "that" next to sloth changes the intended meaning. It implies that the sloth was found in Puerto Rico in 1991. "that" cannot refer to the fossils because the verb after "that" is singular (was found AND even was dated) and not plural. "Was Dated" indicates the PRONOUN NUMBER AGREEMENT ERROR as the SUBJECT fossils is plural. Usage of the Demonstrative Pronoun "THIS" is also wrong here.

D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on
CORRECT. For the following reasons,
1. PRONOUN NUMBER AGREEMENT ERROR : is resolved as have been dated correctly refers to the fossils.
2. Making (the VERB-ing modifier) refers correctly to the subject ("fossils") of the preceding clause.
3. PRONOUN AMBIGUITY ERROR : Here, the pronoun "it" is correctly replaced by the sloth.


E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of
Here, the relative pronoun "which" refers to sloth, making the sentence sound illogical. As it appears "the sloth was dated at...". Usage of WHICH without a preceding comma or a preposition is also incorrect. The overall structure of this option is awkward and hence, INCORRECT. The VERB-ed modifier ("made") is also dangling as its not clear actually what it is modifying as VERB-ed modifiers can modify the preceding noun only.





Hello aceGMAT21,


Great job in presenting such a detailed analysis of this question. :thumbup:

I would just like to add my two cents on a few points of your analysis.


Quote:
1. FOUND can be a VERB or a VERB-ED modifier. As sloth is present next to found, it seems "found" is the verb for sloth. But, sloth cannot do this action of finding. Thus, found is not the verb for sloth. Similarly, found is not even the verb for arms as well as fossils.



I am afraid your analysis is not correct here. The word found cannot be and is not a verb in this official sentence because the context of the sentence makes it absolutely clear.

If we pay attention to structure and the context of the sentence, we will know instantly that found has been used a verb-ed modifier because there is no object for this verb in the entire sentence.


Quote:
2. Found as a VERB-ed MODIFIER can modify any of these 3 : fossils; arm; sloth. But the portion after "and", dated clears this confusion. As dated cannot modify sloth or arm.



A modifier must logically modify an entity. Now the modifiers found and dated form a parallel list in the sentence, indicating that they have been used to modify the same entity. So from the context of the sentence, we understand that whatever has been found has been dated at 34 million years old.

On the basis of this analysis, neither sloth nor arm can be the entity the modifier found is meant to modify because neither a sloth not its arm would exist for that long. It is only the fossils that can exist that long (or even longer).

So logically, found and dated modify fossils only.



Hope this helps. :-)
Thanks.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 22 Apr 2018, 05:23
GMATNinja egmat VeritasPrepKarishma

Quote:

(A) Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

(D)sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on



Is this one of few rare occasions in which coma+verb-ing modifier (coma + making) makes
more sense with subject of the earlier clause - a sloth - than the verb - made in (A)

In (D), the coma+making modifies complete earlier clause and the subject of earlier clause is: Fossils of the arm of a sloth

Can you elaborate why is there a pronoun ambiguity in :
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old,made it the earliest known mammal of the Greater Antilles islands.

Is there any significant distinction between usage of pronoun on / of after mammal?
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 22 Apr 2018, 05:48
Hey,

I've a question regarding the last part of answer D:

"D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on"

So, "making" modifies "Fossils of the arm of a sloth". Isn't the placement a bit far away? I thought the modifier should be placed as close as possibile.

Cheers :)
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 22 Apr 2018, 23:17
adkikani wrote:
GMATNinja egmat VeritasPrepKarishma

Quote:

(A) Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

(D)sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on



Is this one of few rare occasions in which coma+verb-ing modifier (coma + making) makes
more sense with subject of the earlier clause - a sloth - than the verb - made in (A)

In (D), the coma+making modifies complete earlier clause and the subject of earlier clause is: Fossils of the arm of a sloth

Can you elaborate why is there a pronoun ambiguity in :
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old,made it the earliest known mammal of the Greater Antilles islands.

Is there any significant distinction between usage of pronoun on / of after mammal?


In option (A), "found in .." and "dated at ..." are two parallel modifiers.
The main clause is "Fossils of the arm of a sloth ... made it the earliest known mammal of the Greater Antilles islands"
This makes no sense.

What made it the earliest known mammal? Dating the fossil at 34 million years. This is clarified in (D)
Fossils of the arm of a sloth ... have been dated at 34 million years old, making the sloth the earliest known mammal ...
The participle "making the sloth ..." modifies the entire preceding clause.

"mammal of the islands" seems to imply that the mammal belongs to the islands, perhaps exclusively. I would much rather prefer the use of "on" which implies that we are talking about the mammals found on the islands.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 28 Apr 2018, 05:56
Hi experts

Quote:
A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of


I did not pick them up because i think it is illogical to say fossils can make some opinions, while the found of fossils can make some opinions

mikemcgarry, GMATNinjaTwo, GMATNinja, MagooshExpert Carolyn,
sayantanc2
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Would you please confirm ?

Thanks in advance

Have a nice day
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 31 May 2018, 10:49
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zoezhuyan wrote:
Hi experts

Quote:
A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of


I did not pick them up because i think it is illogical to say fossils can make some opinions, while the found of fossils can make some opinions

Would you please confirm ?

Thanks in advance

Have a nice day
>_~

I'm not quite sure what you mean by "opinions" in this question. I assume you're referring to the idea that the discovery of the fossils "made the sloth the earliest known mammal of the Greater Antilles islands"...? That's not an opinion, exactly, but I agree that it's illogical to say that "fossils... made the sloth the earliest known mammal..."

Here's (D) again:

    "Fossils of the arm of a sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on the Greater Antilles Islands."

Notice that the phrase "making the sloth the earliest known mammal..." is now a modifier, not a verb phrase. That phrase is just modifying the previous clause: "Fossils of the arm of a sloth... have been dated at 34 million years old..." And that actually makes a lot of sense: the fossils are really freaking old, and that fact makes the sloth the earliest known mammal of the Greater Antilles. Because that last "-ing" phrase modifies the entire previous clause, the sentence isn't saying that the fossils themselves "made" the sloth the earliest known mammal -- it's saying that the act of dating the fossils made it the earliest known mammal.

I hope this helps!
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 31 May 2018, 14:47
fallenx wrote:
Hey,

I've a question regarding the last part of answer D:

"D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on"

So, "making" modifies "Fossils of the arm of a sloth". Isn't the placement a bit far away? I thought the modifier should be placed as close as possibile.

Cheers :)



Hello fallenx,

I am not sure if you still have this doubt. Here is the answer nonetheless. :-)


In Choice D, comma + making... is an action modifier, and hence, it modifies the action - have been dated at - in the preceding clause.

Please note that comma + making... is not a noun modifier that needs to be placed closer to Fossils of the arm of the sloth.

As an action modifier, comma + making... suggests that because these fossils are so very old, this information makes the sloth the earliest known mammal in the said region.


Hope this helps. :-)
Thanks.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 22 Nov 2018, 20:15
GMATNinja wrote:
I’ve always had a soft spot for this question, just because it has such a wide variety of issues and errors. It also has an interesting little verb tense thing that really doesn’t matter at all: you could easily fixate on the difference between "was dated" (past tense) and "has/have been dated" (present perfect tense), but you don't have to choose between them at all. There are plenty of other issues to worry about instead.

Quote:
(A) sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

The “it” (which presumably refers back to the sloth) is the first thing that jumps out at me. “Fossils of the arm of a sloth… made [the sloth] the earliest known mammal…” Huh? That makes no sense. How the heck would the fossils of a sloth make the sloth the earliest known mammal of the Greater Antilles?

The much smaller issue is that I see no real need for that first comma, but that’s unlikely to ever be a deciding factor on a GMAT question. But the nonsensical main clause is enough to wipe out (A).

Quote:
(B) sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on

This time, the pronoun “they” is the first thing that catches my eye. Who the heck is “they”? The fossils?

Plus, we have a subject-verb problem: “fossils… has been dated” is spectacularly wrong. (B) is gone.

Quote:
(C) sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of

Subject-verb fail again: “fossils… was dated.” Nope.

But there’s more: the phrase “that was found in Puerto Rico in 1991” seems to modify the sloth itself, and that makes no sense. Unless you think that the sloth had actually been alive for 34 million years. Maybe moving really slowly helps you live longer?

Finally, the word “this” is used as a singular pronoun, and that’s an unacceptable use of the word “this” on the GMAT. I’ve only ever seen “this” used as an article on the GMAT (“this week” or “this magnificent GMAT forum”), but never as a pronoun.

So we have lots of good reasons to eliminate (C).

Quote:
(D) sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

This one looks pretty good. The subject-verb agreement works: “fossils… have been dated at 34 million years old…” Cool. The modifier “found in Puerto Rico in 1991” is nicely set apart with commas, so it seems to refer to the entire phrase “fossils of the arm of a sloth”, and not just the sloth itself, as we saw in (C).

And the last part of the underlined portion (“making the sloth the earliest known mammal…”) actually names the sloth instead of using a pronoun, and that adds a bit of extra clarity. It might not be strictly necessary, but it’s nice. We can keep (D).


Quote:
(E) sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

Thanks to the modifier “which”, which typically modifies the immediately preceding noun, it really sounds like the sloth itself was found in Puerto Rico in 1991, and that makes no sense. (I also can’t make much sense of the comma placement in that part of the sentence, but again, comma placement isn’t really a major emphasis on GMAT SC.)

We also have the same problem that we had in (A): “fossils… made the sloth the earliest known mammal…” That’s nonsense, too.

So we can ditch (E), and (D) is our answer.


Hi, Ninja.
I actually did one question about the use of date.
Actually, date can not be used as "have dated at " or "have been dated at..' since" past perfect implies that this is not the case anymore.
So I eliminated D at once....This one is really made me mad!! Tense is also an absolute judgement to eliminate answers.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 12 Jan 2019, 03:29
GMATNinja

Thank you for your kind explanation.

However, I'm a little bit confused for a part of your explanation.

In explanation for choice A , you mention that the phrase "Fossils of the arm of a sloth… made [the sloth] the earliest known mammal…" makes no sense.

But, In choice D , you accept that the pharse" making the sloth the earliest known mammal on" is correct.

Those two explanations seem quite contradict.

Please help me clarify the issue.

Thank you so much.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 27 Jan 2019, 16:49
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Hello Everyone!

Let's take a look at this question, one issue at a time, and narrow it down to the correct choice! To begin, here's the original question with the major differences between the options highlighted in orange:

Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
B. sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on
C. sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of
D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on
E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

After a quick glance over the options, a few key differences jump out:

1. Comma placement and verb choice after "sloth" (essential vs. non-essential clauses)
2. dated / has been dated / was dated / have been dated (verb tense)
3. made it / making it / making this / making the sloth / made the sloth (verb tense & pronouns)
4. of / on / known on (idioms)


Let's start with #1 on our list, which is to focus on how each sentence handles essential and non-essential clauses. Whenever we see a phrase in the middle of a sentence that's between two commas, it's supposed to be a non-essential clause.

This means that if we removed the phrase, the sentence would remain a complete sentence and wouldn't lose its intended meaning. A quick way to check this is to cross out any non-essential clauses you can find, and read what's left over. If it still makes sense, keep it for later. If it becomes a sentence fragment, or the meaning is totally changed, eliminate it. To make this easier, I've added in the non-underlined portions of the sentence:

A. Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.

This is INCORRECT because the meaning of the sentence is altered by taking out the phrase "and dated at 34 million years old." By removing that phrase, we're simply saying that the presence of sloth fossils found in 1991 is enough proof that they are the earliest known mammals on the islands. But how do we know that? Because they were dated at 34 million years old. If we remove that bit of information, what's left over is vague and confusing for readers.

B. Fossils of the arm of a sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on the Greater Antilles islands.

This is INCORRECT because when we eliminate the non-essential clause, we can clearly see that there is a subject-verb agreement problem. This sentence uses the singular "has been dated" with the plural "Fossils," so let's rule this one out.

C. Fossils of the arm of a sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of the Greater Antilles islands.

This is INCORRECT because, if we read the sentence with the non-essential phrase crossed out, it doesn't make sense. It's actually missing a verb! Therefore, let's eliminate this option.

D. Fossils of the arm of a sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on the Greater Antilles islands. --> OKAY

E. Fossils of the arm of a sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of the Greater Antilles islands. --> OKAY

We can eliminate options A, B, & C because they have problems when dealing with non-essential clauses.

Now that we've narrowed it down to 2 options, let's take a closer look at what we have left:

D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

This is CORRECT! The non-essential phrase, "found in Puerto Rico in 1991" truly is a non-essential piece of information. The important points (fossils were found, they were dated at 34 million years old, we now know they were the earliest mammals from the island) are all there and punctuated correctly. The sentence also uses the correct verb tense "have been dated" to show that the fossils were dated after they were found, but before the present, which is what we're looking for. It also correctly uses "making" to turn the last clause into an -ing modifier that refers back to the previous phrase, which is what we're looking for.

E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of

This is INCORRECT for one main reason - it contains two competing verbs! It correctly uses commas to make the phrase "found in Puerto Rico in 1991" a non-essential clause. However, it has two verb phrases (was dated at 34 millions years old / made the sloth the earliest known mammal...) without anything to connect them together. The last phrase should start with "making" to change it to a modifier that shows cause and effect. The fossils were dated at 34 million years old, and that led to them being known as the oldest mammals on the islands. Without the -ing modifier, it's unclear what actions led to what results.


There you have it - option D is the correct choice! This is an incredibly complex question, but if you can focus on the differences between the options, you can narrow down your options to only a couple you can focus on in more detail.


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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 02 Apr 2019, 01:06
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Rebekah wrote:
Hi, Ninja.
I actually did one question about the use of date.
Actually, date can not be used as "have dated at " or "have been dated at..' since" past perfect implies that this is not the case anymore.
So I eliminated D at once....This one is really made me mad!! Tense is also an absolute judgement to eliminate answers.

It sounds like you might be confusing present perfect tense ("have + verb" or "has + verb") with PAST perfect tense ("had + verb"). An action in past perfect tense ("had dated", for example) must be completed in the past before some other action or marker. But that tense doesn't appear here at all! Instead, we have the present perfect tense "have been dated" -- and whenever you see this tense, it indicates an action that starts in the past and continues into the present.

Again, we could debate whether "have been dated" is ideal here. It basically implies that "dating" an object (i.e., determining its age) is an ongoing process that isn't necessarily completed in a single instant. I suppose that's reasonable enough, since the object continues to get older, and our understanding of its age might continue to evolve. At the very least, it isn't a DEFINITE error to use the present perfect "have been dated" here, especially since there are TONS of other decision points in this question.

And yes, there are times when verb tenses can lead you to definite errors, but that certainly isn't always the case. For more on verb tenses, check out this video.

ballest127 wrote:
GMATNinja

Thank you for your kind explanation.

However, I'm a little bit confused for a part of your explanation.

In explanation for choice A , you mention that the phrase "Fossils of the arm of a sloth… made [the sloth] the earliest known mammal…" makes no sense.

But, In choice D , you accept that the pharse" making the sloth the earliest known mammal on" is correct.

Those two explanations seem quite contradict.

Please help me clarify the issue.

Thank you so much.

If we strip out some of the modifiers in choice (A), we have this:

    “Fossils… made the sloth the earliest known mammal…”

I still think that doesn’t make any sense. How could fossils possibly “[make] the sloth the earliest known mammal of the Greater Antilles…”? That suggests that fossils somehow led to the existence of the sloth, and that’s clearly nonsense.

The structure in (D) is completely different:

    “…making the sloth the earliest known mammal...”

“Making” is a modifier here, and it modifies the entire preceding clause: “Fossils of the arm of a sloth were dated at 34 million years old…”. And that makes perfect sense: “making the sloth the oldest known mammal of the Greater Antilles” just tells us more information about the consequences of discovering that the fossils were 34 million years old.

Maybe you’re thinking that the “-ing” modifier (“making”, in this case) can only modify a noun? That’s not actually the case. For more on this issue, check out this post or this post.

I hope this helps!
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 02 Apr 2019, 05:10
Hi GMATNinja,

Thank you for your kind explanation.

I know that comma + present participle can modify the preceding clause, not just only noun.
However, I understand that comma + present participle must make sense with the subject of that preceding clause.

In D, the subject of the sentence is "fossil".
That is why I think that the fossil is the doer of "making the sloth...."

Please correct me if I'm wrong.

Really appreciate.

Thank you.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 11 Jun 2019, 23:06
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.


A. sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

Fossils of the arm of a sloth found in Puerto Rico in 1991-->made it the earliest known mammal: No wrong,And what this It stand for?

B. sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on: Wrong They?? referring to??

C. sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of
Was found : Passive form and same issue as A. Sloth.....1991--> making....(Wrong)
D. sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on
Correct : have been dated at 24 million years ago.
E. sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of
Obviously Wrong. Look at the placement of Which..
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Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 22 Jul 2019, 01:03
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Wisdom of Ron about PRESENT PERFECT in option D
In describing a past event that is no longer occurring, we can use either the present perfect or the simple past. the difference between the two is one of semantic meaning:
-----the present perfect (has/have VERBed) is used if the event still has a tangible impact or influence on, or relevance to, the present state of affairs.
-----the simple past is used if the event does NOT have any tangible impact/influence/relevance in the present.
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 13 Oct 2019, 21:05
Hi,

@empowergmat verbal in this question in option D and E; the phrases "have been dated at", "was dated at" are in comma pairs why didn't we omit these? also is it like the information in non essential phrases always acts as a modifier and when it doesn't then it is not considered as a non-essential phrase?
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 15 Oct 2019, 12:02
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sampriya wrote:
Hi,

@empowergmat verbal in this question in option D and E; the phrases "have been dated at", "was dated at" are in comma pairs why didn't we omit these? also is it like the information in non essential phrases always acts as a modifier and when it doesn't then it is not considered as a non-essential phrase?


Hello sampriya!

The reason we don't eliminate those phrases is that they are ESSENTIAL clauses - they contain the sentence's main verb! Not all phrases with commas on both sides are non-essential phrases - ONLY the ones that don't contain the subject or verb!

Also, modifiers are just one type of non-essential phrase. There are many others, and they follow the same basic rule - if you can eliminate them without creating a sentence fragment, then they are non-essential. If eliminating a phrase also eliminates the subject or verb (which is what would happen if you crossed out those two phrases), then it is essential and needs to stay in the sentence.

I hope that helps clear things up!
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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated  [#permalink]

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New post 09 Nov 2019, 00:16
nakib77 wrote:
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.


(A) sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of

(B) sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on

(C) sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of

(D) sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on

(E) sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of


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https://www.nytimes.com/1996/04/16/science/mammal-bones-found-in-amber-for-first-time.html

Fossils of the arm of a sloth, found in Puerto Rico five years ago, have been dated at 34 million years old, making it the earliest known mammal on the islands and presumably an inhabitant at the time of the hypothesized separation, Dr. MacPhee said. The age of the amber-preserved mammal, though not precise, could be further evidence of when these migrations occurred, particularly of when they might have ended.




mammals of island eliminate A,C,E.
In B They isn't correct usage.
D is correct option .


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Re: Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated   [#permalink] 09 Nov 2019, 00:16

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