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A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the world has ever seen.

(A) believed to be
(B) and that is believed to be
(C) and it is believed to have been
(D) which was, it is believed,
(E) which is believed to be



What is the structure of this sentence? We begin with an appositive ‘a huge flying …ago’ placed next to the subject which is ‘the Quetzalcoatlus.’
The main clause tells us two things about the Quetzalcoatlus – its wingspan and that it was the largest flying creature the world has ever seen. We can give the two qualities of the Quetzalcoatlus as two clauses (done by options (B) and (C)) or one as a modifier and the other as the main clause (done by options (A), (D) and (E)).

(A) believed to be

Option (A) uses the past participle modifier ‘believed’ which seems to be modifying the noun closest to it i.e. ‘wingspan.’ But we have discussed that past participle at the end of the sentence could modify the subject of the previous clause too so we may not want to eliminate based on that. The use of ‘believed to be’ gives the impression that the Quetzalcoatlus is still alive.
For example, ‘he is believed to be the tallest man in the world’ tells us that he is alive today and is the tallest today. ‘He is believed to be the tallest man the world has ever seen’ means he is the tallest not just today but in the entire history of mankind.
‘He is believed to have been the tallest man’ means he was the tallest at one time. Now, either he is not alive or not the tallest and someone else is the tallest.
Since we know that the Quetzalcoatlus is extinct now, we can eliminate option (A). Options (B) and (E) also have this error.

(D) which was, it is believed,
(E) which is believed to be


Options (D) and (E) use ‘which’ relative clauses. ‘which’ usually modifies the noun preceding it and hence, it seems that we are talking about the wingspan in the ‘which’ modifier. But we know that we are talking about the Quetzalcoatlus.

(B) and that is believed to be

Option (B) has the same ‘believed to be’ error that options (A) and (E) have. Also, option (B) uses ‘that’ as the subject of the second clause to refer back to the subject of the previous clause. But ‘that’ is a demonstrative pronoun which indicates distance in time or space (relative to speaker) e.g. ‘That is my car.’
We will need to use the personal pronoun ‘it’ as the subject of the second clause to refer back to the subject of the previous clause. This is done in option (C).

(C) and it is believed to have been

Further, in option (C), the use of the present tense ‘is believed’ is correct because the belief is held in the present. Also, ‘to have been’ is the perfect infinitive. We have learnt that we can use perfect infinitives for things that happened in the past. The Quetzalcoatlus was the largest flying creature in the past. It is extinct now. So perfect infinitive is acceptable here.

Answer (C)
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C it will be ...

the sentence uses '' the quetzalocatlus HAD a wingspan'' the use of ''HAD'' makes it past perfect and the sentence should be in perfect unision with the tense flow....


A) ''believed to be'' does not sound right and lacks a pronoun too

B) seems right but the use of ''that'' does not substitute for the right pronoun...

D) the use of ''which was'' tries to say ''the wingspan'' and not the Q.....s was the largets flying reptile or watever...

E) same confusion...

C) has ''it'' pronoun reference and also the use of ''have been'' suits for the use ''the world has seen '' both of which are in the past tense...


any other expalnation is welcome pls...

hope that helps!

Have fun :)
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Agree with C as it is the only choice which introduces a personal pronoun to refer to the Quetzalcoatlus. A's participial phrase and B,D and E's relative pronoun improperly refers to "wingspan" and hence make the wrong comparison
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IMO C
A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the world has ever seen.
(A) believed to be --> believe here will be incorrectly implied as verb for subject Quetzalcoatlus because it is also in past tense as 1st verb had, making the whole sentence having a wrong meaning
(B) and that is believed to be --> that here wrongly modifies for all the clause the Quetza ... 36 feet, while it should modifies only for Quetzacoatlus
(C) and it is believed to have been -->best choice. It clearly refers to Quetzalcoatlus. Is believed here is no problem because it reflects that such action occurs in the present time. Besides, present perfect here is correctly used because the 2nd clause is also parallel with a sub-clause the world has ever seen, modifying for the 2nd clause
(D) which was, it is believed --> which here refers to the nearest noun 36 feet, making the wrong meaning for the whole sentence
(E) which is believed to be -->the same error as D

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Yes, C is better option

(A) believed to be - incorrectly placed modifier, closer to wingspan than to reptile.
(B) and that is believed to be - ambiguous use of that, not referring to the reptile
(C) and it is believed to have been - correct
(D) which was, it is believed, - use of was and is together. sounds awkward
(E) which is believed to be - sounds like wingspan is believed to be....
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A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the world has ever seen.

(A) believed to be - 'believed' is incorrectly modifying '36 feet'

(B) and that is believed to be - awkward

(C) and it is believed to have been - 'it' correctly refers to 'Quetzalcoatlus'. 'it' cannot refer to 'wingspan' because 'wingspan' is the object of the earlier clause. So the pronoun 'it' is unambiguously refering to the noun 'Quetzalcoatlus'

(D) which was, it is believed, - 'which' is incorrectly modifying '36 feet'

(E) which is believed to be - - 'which' is incorrectly modifying '36 feet'
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Great question!

Here's my logic for which C is ok grammatically:

C: "A high–flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, and it is believed to have been the largest flying creature the world has ever seen."

First, let's get to the core of this sentence. Everything up to "years ago" is a warm-up that can be ignored. So now we have:

"The Quetzalcoatlus had a wingspan of 36 feet, and it is believed to have been the largest flying creature the world has ever seen."

Now, we essentially have an interesting case of parallelism here:

The Quetzalcoatlus...
1. had a wingspan of...
2. is believed to have been...

Since we are dealing with parallelism, we really only have one subject in the sentence: the Quetzalcoatlus. Thus, both the "had" and "is" clauses refer to the bird itself.

That help?

Brett
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I've never come across an instance where you can have two objects in a sentence and a single ambiguous pronoun. I've also never come across an instance where you can have an object and a subject of the same type and have the pronoun be unambiguous. Quite simply, the rule is this: A pronoun must clearly refer to one, and only one, antecedent.

I suppose an example would be:

"Bill gave Ted $5, and he said thank you."

Here, "Bill" is the subject and "Ted" is the object. The "he" is still ambiguous even though we have only one "subject." Although we know logically that Ted is the one who would need to say "thank you," grammatically there's some ambiguity there.

Brett
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I've never come across an instance where you can have two objects in a sentence and a single ambiguous pronoun. I've also never come across an instance where you can have an object and a subject of the same type and have the pronoun be unambiguous. Quite simply, the rule is this: A pronoun must clearly refer to one, and only one, antecedent.

I suppose an example would be:

"Bill gave Ted $5, and he said thank you."

Here, "Bill" is the subject and "Ted" is the object. The "he" is still ambiguous even though we have only one "subject." Although we know logically that Ted is the one who would need to say "thank you," grammatically there's some ambiguity there.

Brett

OK, so how can "it" be unambiguous here?

The Quetzalcoatlus had a wingspan of 36 feet, and it is believed to have been the largest flying creature the world has ever seen.

If the "it" were removed, it would be better: The Quetz had X, and is Y.

Thoughts on that?

Thanks in advance.
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Thx Raptor. Picking c is not the issue. My question pertains to why "it" in C is not ambiguous, i.e., it possesses a valid "clear antecedent" as stated somewhere in the OG; in terms of choosing b/w wingspan vs. the Q in relation to "IT":

The Q <------------------------ "IT" ---------------------------> Wingspan
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noboru and gmat1011 -

The clause says "it is believed to have been the largest flying creature the world has ever seen."

The antecedent of a pronoun has to be clear, unambiguous, and logical. You cannot logically say "The wingspan is believed to be the largest flying creature..." because a wingspan is not a creature. As such, "wingspan" would be a nonsensical antecedent.

Similarly, if a sentence said:

"The beaver knocked over the tree, and then it ate it." --> Technically, both "its" could be considered ambiguous. However, I'd argue that since a tree cannot eat something, you're pretty safe writing this sentence.

Feeling more confident about this one?
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monarc,

Good question. Let's dive into the difference between "have been" and "had been"...

"Have been" is used for an action from the past that is still in progress. For example:

"I have been walking since 2:00 p.m., and I'm not tired yet!"
"I have been searching for my dog all month, but we haven't found him!"

Notice how in these examples, there is no past tense verb in the sentence and I am still walking/searching. As a result, I use "have been" (present perfect tense).

On the other hand, "had been" is used for an action that happened before something else in the sentence occurred. For example:

"I had been walking for six hours before I stepped on a rock and sprained my ankle."
"I had been searching for nine hours before I decided to give up."

Notice how in these examples, you do have a past tense verb in the sentence ("stepped" and "decided") that describes something that occurred after the first thing started. Since you have an ongoing action in the way past and another action in the past that comes later in time than the first action, you need to use "had been" (past perfect tense).

Finally, notice that it doesn't matter which part comes first; the past perfect part can follow the past tense part in the sentence even though the order in which they occurred is the reverse. Just remember that if there are two things that happened at different times in the past, you'll need to use past perfect somewhere. For example:

"Before I stepped on a rock and sprained my ankle, I had been walking for six hours."
"I decided to give up after I had been searching for nine hours."

Happy studying!

Brett
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Here's the explanation.

Let's consider the question stem, specifically the underlined part. Here, 'believed to be' is an adjective modifier/clause and it is supposed to modify the noun 'Quetzalcoatlus'. However, the adjective modifier/clause should modify the noun immediately before. In this case, the noun before it is '36 feet'. Hence the modifier incorrectly modifies the wrong noun.
Now, let's look for an answer which will resolve this issue.

Option A - incorrect for the reason mentioned above.

Option B - This option connects the clause 'believed to be ...' using the conjunction 'and'. However, 'that' in the answer incorrectly modifies the clause 'the Quetzalcoatlus had a wing span of 36 feet' instead of only modifying the noun 'Quetzalcoatlus'. Hence this is incorrect as well.

Option C - This option correctly modifies the noun 'Quetzalcoatlus' by using the pronoun 'it' for reference and connecting the adjective modifier using the conjunction 'and'.

Option D - this is very ambiguous and also incorrectly uses the relative pronoun 'which' to modify the noun '36 feet' immediately preceding it.

Option E - this option also incorrectly modifies the noun '36 feet' immediately preceding the adjective modifier 'believed to be ...'.

Hope this helps.

Cheers!
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C. All of the others incorrectly modify (or refer to) the wingspan of 36 feet, rather than the Quetzalcoatlus itself. "It," unlike "that," can refer back to the subject of the sentence.
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A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the world has ever seen.

(A) believed to be
Incorrect: This is saying that "36 feet" is "believed to be the largest flying creature the world has ever seen. Incorrect modifier.

(B) and that is believed to be
Incorrect: The use of "that' is incorrect. "That" cannot refer back to the reptile. "It" would have to be used instead.

(C) and it is believed to have been
Correct:

(D) which was, it is believed,
Incorrect: Again, incorrect modifier. Says "36 feet" was believed . . .

(E) which is believed to be
Incorrect: Modifier issue again
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Hi,

Let's take a look. It seems like we are dealing with modifiers.

3. A huge flying reptile that died out with the dinosaurs some 65 million years ago, the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the world has ever seen.

(A) believed to be
this is inappropriately referring to 36 feet when it should refer to the reptile
(B) and that is believed to be
Incorrect. What is that referring to? It could refer to the wingspan but we want a pronoun to refer to the reptile
(C) and it is believed to have been
Correct, put the Quetzalcoatlus in for "it" and this reads well
(D) which was, it is believed
Wrong because which is inappropriately referring to 36 feet
(E) which is believed to be
Wrong because which is inappropriately referring to 36 feet

Let me know if you need more advice on this.

Happy Studies,

HG.
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When we say, believed to be, we mean to say that whatever is being talked about is currently existing. But those animals are said to have died along with dinosaurs; so the use of believed to be is incongruous. Believed to have been denotes something that was in the past only and not presently and therefore, the appropriate idiom to use in this case
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