Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria take an active part in the process. A. as a method of the extraction of minerals, it was well established B. as a method of the extraction of minerals well established C. was a well-established method of mineral extraction D. was a well-established method of extracting mineral that was E. had been a method of mineral extraction, well established

Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria take an active part in the process. Meaning Analysis: Leaching is a process used to extract copper from the drainage water of mines. This method was established in the eighteenth century. 25 years ago miners realized that bacteria play an active role in this method. Prior, they had no clue! Sentence Structure: Leaching (subject) , the recovery of copper from the drainage water of mines, (noun + noun modifier modifying the subject "leaching") (notice the modifier is in a comma pair this clearly means that it is just acting as some additional information) as a method ("as" is used as a comparison marker ; "as + noun" is used to state the function of the entity. Here "leaching" is a "method") , it (subject) (it refers to leaching) (element 1 of comparison) was well established (verb) as early as (comparison marker) the eighteenth century (element 2 of comparison) , but until about 25 years ago (contextual word "but" indicates a change of tone/idea/direction) miners (subject) did not realize (verb) that (connector) bacteria (plural subject) take (plural verb) an active part in the process. (object of the sentence) We have the subject "leaching" without a verb and thus there is a SV error. Also notice "method of the extraction", this structure just makes the sentence inferior. Same errors of choice (A) are repeated. Note that "established" is the adjective modifying "leaching" and is not acting as a verb. "well" on the other hand is the adverb modifying the adjective "established" Correct. The subject "leaching" is given a simple past tense verb "was established". Notice, by removing article "the" we have "a method of mineral extraction" this is much better compared to "a method of the mineral extraction" Takeaway: When "the" is used we are trying to go specific. This means that if we say "the leaching" we aren't talking about "leaching" in general rather, we are talking about one specific type of "leaching and that is certainly illogical. (1) Buy me a book --> buy me any book. (2) Buy me the book --> we are talking about a specific book out here. "That" refers to "mineral" and thus the sentence "was as early as the eighteenth century" refers to "mineral". This is clearly illogical. We want to say that "leaching method" was established in the eighteenth century and not that "the minerals extracted from this method" was established in the eighteenth century. If one focuses on the meaning of the sentence he/she will be able to eliminate this option. By using past perfect tense "had been" we are now saying that the "leaching" at one time was a method of extracting minerals and now it no longer is. This is certainly not what the author is trying to convey. Correct choice: (C) Learning:- a noun + noun modifier is essentially a noun modifier that modifies a noun. " Ron , the smart guy with brown hair , is studying for the test. " The smart guy is a noun and "with brown hair" is a prepositional phrase modifying the noun "the smart guy". And combined this entire modifier " the smart guy with brown hair " is modifying our main subject "Ron" Well explained by egmat in the following links:- 1. What is a noun + noun modifier https://e-gmat.com/blogs/noun-noun-modi ... ny-entity/ 2. Noun + noun modifier Vs an action modifier https://gmatclub.com/forum/noun-noun-mo ... 37569.html

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Leaching, the recovery of copper from the drainage water of mines, as

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bad_math

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I still struggle with the awkwardness of C when you remove the modifier:

Quote:

Leaching was a well-established method of mineral extraction as early as the eighteenth century, ...

It just doesn't sound right, I know GMAT wants you to fall for this trick and I keep doing it. Even once I know this is the correct answer, I still don't feel comfortable with the choice

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04 Jun 2019, 12:48

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Would I be wrong to say that the past perfect in choice E is wrong because the point of time is set by the sentence itself?

<...> ,well established as early as the eighteenth century as early as the eighteenth century, <...>

So basically we know that the method existed as early as the XVIII c. and it was well established sometime in that period. Thus no need for the past perfect.

Thanks

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Hi, I am a little confused with the use of "was' in option c. I want to understand is the use of "was" correct? because what confused me is the fact, that leeching is still a method of extraction and has not ceased to be one. So shouldn't i use "is" or am i missing out on something.

Even though i got the answer right by elimination, but this thought is just bugging me.

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11 Sep 2019, 18:35

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generis VeritasKarishma AjiteshArun

Quote:

I am confused between selecting correct verb tense here. Can you help me to clarify below queries:
1. Whenever, we have a specific time marker as UNTIL X years, use of simple past / past perfect is permissible.
2. Why do we choose WAS over HAD BEEN ? We are already given two time frames :
a. Until 18th century.
b. 25 years ago.
Obviously, (18th century) comes earlier than (25 years ago), so use of past perfect seems more correct
to denote earlier of two actions.
OR
Has establishment of method and realization of miners need not be sequenced?
Where did I falter in above?

KarishmaB

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12 Sep 2019, 01:44

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adkikani

generis VeritasKarishma AjiteshArun

Quote:

You need to use past perfect when you need to establish anterior time to some time in the past. Past perfect shows completion of an action/state prior to a point of time in past.

You would use past perfect for "... had been a well established method until 25 years ago researchers realised that a lot of mineral is wasted ..." etc.
So if it stopped being a well established method 25 years ago, you will use past perfect.

Also, often past perfect is used to show sequence of two actions, both in the past or to show an action or state prior to a point of time in the past. If this sequence is obvious, you don't "NEED" to use it there.

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Let me explain,

1. leaching is method to extract minerals in 18th century. ie, old technology.
2. Until 25 years it was not well accepted.

It seems like past perfect tense, right ? but No.
Past perfect tense is used only when the event happened in the past and completed there itself ( 2 time framed events ). option (E) out

Leaching is an old method used to extract minerals in 18th century, it was not accepted until 25 years ago. Just simple past tense. Option C.

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Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria take an active part in the process.

Meaning Analysis: Leaching is a process used to extract copper from the drainage water of mines. This method was established in the eighteenth century. 25 years ago miners realized that bacteria play an active role in this method. Prior, they had no clue!

Sentence Structure:
Leaching (subject)
, the recovery of copper from the drainage water of mines, (noun + noun modifier modifying the subject "leaching") (notice the modifier is in a comma pair this clearly means that it is just acting as some additional information)
as a method ("as" is used as a comparison marker ; "as + noun" is used to state the function of the entity. Here "leaching" is a "method")
, it (subject) (it refers to leaching) (element 1 of comparison)
was well established (verb)
as early as (comparison marker)
the eighteenth century (element 2 of comparison)
, but until about 25 years ago (contextual word "but" indicates a change of tone/idea/direction)
miners (subject)
did not realize (verb)
that (connector)
bacteria (plural subject)
take (plural verb)
an active part in the process. (object of the sentence)

Quote:

A. as a method of the extraction of minerals, it was well established

We have the subject "leaching" without a verb and thus there is a SV error. Also notice "method of the extraction", this structure just makes the sentence inferior.

Quote:

B. as a method of the extraction of minerals well established

Same errors of choice (A) are repeated. Note that "established" is the adjective modifying "leaching" and is not acting as a verb. "well" on the other hand is the adverb modifying the adjective "established"

Quote:

C. was a well-established method of mineral extraction

Correct. The subject "leaching" is given a simple past tense verb "was established". Notice, by removing article "the" we have "a method of mineral extraction" this is much better compared to "a method of the mineral extraction"

Takeaway:

When "the" is used we are trying to go specific. This means that if we say "the leaching" we aren't talking about "leaching" in general rather, we are talking about one specific type of "leaching and that is certainly illogical.
(1) Buy me a book --> buy me any book.
(2) Buy me the book --> we are talking about a specific book out here.

Quote:

D. was a well-established method of extracting mineral that was

"That" refers to "mineral" and thus the sentence "was as early as the eighteenth century" refers to "mineral". This is clearly illogical. We want to say that "leaching method" was established in the eighteenth century and not that "the minerals extracted from this method" was established in the eighteenth century.

Quote:

E. had been a method of mineral extraction, well established

If one focuses on the meaning of the sentence he/she will be able to eliminate this option. By using past perfect tense "had been" we are now saying that the "leaching" at one time was a method of extracting minerals and now it no longer is. This is certainly not what the author is trying to convey.

Correct choice: (C)

Learning:-

a noun + noun modifier is essentially a noun modifier that modifies a noun. "Ron, the smart guy with brown hair, is studying for the test." The smart guy is a noun and "with brown hair" is a prepositional phrase modifying the noun "the smart guy". And combined this entire modifier "the smart guy with brown hair" is modifying our main subject "Ron"

Well explained by egmat in the following links:-
1. What is a noun + noun modifier https://e-gmat.com/blogs/noun-noun-modi ... ny-entity/
2. Noun + noun modifier Vs an action modifier https://gmatclub.com/forum/noun-noun-mo ... 37569.html

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11 Nov 2020, 10:29

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nocilis

The sentence is speaking about LEACHING as an extraction tool of minerals. Option C expresses the intended meaning most precisely.
A. "It' has no clear antecedent.
B. Awkward construction.
C. CORRECT.
D. Unnecessarily passive form is used with that.
E. It was not two event of one in the past.

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19 Apr 2021, 10:32

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"was a well-established method of mineral extraction as early as the eighteenth century
" doesn't quite sound right. could someone help what im missing on this question.

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NikhilJose

"was a well-established method of mineral extraction as early as the eighteenth century
" doesn't quite sound right. could someone help what im missing on this question.

Hi Nikhil, are you missing leaching above?

The sentence is:

Leaching was a well-established method of mineral extraction as early as the eighteenth century.

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I had trouble with C. We typically say '...established as early as'. C says :
"...was a well-established method of mineral extraction as early as"

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Hi Experts,

Final structure: "Leaching was a well-established method of mineral extraction as early as the eighteenth century" seems a bit awkward. Could you please help?

Here "well-established" is used to modify the noun phrase "method of mineral extraction", so how does this correct answer make sense as "established as early as 18th century?

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31 Jul 2022, 19:11

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KarishmaB Ma'am,
In option C, what is "as early as 18th century" modifying?
If it is modifying the "method of extraction", then in option D too "that was as early as..." should modify the method.
What is wrong with option D then?

Please evaluate where am I going wrong.

KarishmaB

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krndatta

'as early as 18th century' is an adverb modifying the verb 'was.' It answers the question - 'when was the method well established?'
Leaching was a well established method as early as the 18th century.

(D) says 'Leaching was a well established method that was as early as 18th century' - This doesn't make sense. That was what as early as 18th century? Popular/unique/beneficial...? Here 'as early as 18th century' does not answer 'when was the method well established?' We have started a new 'that clause.'

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KarishmaB Ma'am,

Doesn't the "that clause" modify "the method"?
The method was as early as 18th century?

KarishmaB

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krndatta

KarishmaB Ma'am,

Doesn't the "that clause" modify "the method"?
The method was as early as 18th century?

Yes, 'that' does stand for 'the method.' Here is the clause you get:

The method was as early as 18th century.

Does this make sense? The method was what?

The method was used as early as 18th century.
The method was popular in the18th century.
etc.

When your main verb is a 'to be' verb (was), you need an equivalence creating noun or an adjective.

e.g.
He is a good man. (He = a good man)
He is happy. (happy describes man)

Can you use just an adverb? What about:

He was yesterday. ('yesterday' is an adverb)
Does this make sense? What was he yesterday? 'He was late yesterday' OR 'He was happy yesterday' etc.

The same is the problem with 'the method was as early as 18th century.'

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KarishmaB

krndatta

KarishmaB Ma'am,

Doesn't the "that clause" modify "the method"?
The method was as early as 18th century?

Then how is C option different from D option?

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nocilis

I got it wrong but I understood the process now. Even though I choose E in my first try, now I see that is the easiest to eliminate
because past perfect continuos is used for action that was occurring in the past when something interrupted it, but the second part of the sentence is not an action or something that interrupted the well stablished method. Eliminate E

after the first modifier, we need a verb, otherwise, the sentence would have 2 modifiers in a row, which make the sentence not clear. So eliminate A and B

Between C and D, they differ after "of ", mineral extraction refers to the process and extracting mineral refers to an action, we are talking about the process, and also D repeat "was" and also say that was as early as the eighteen century" makes no sense.

so IMO C

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