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Leaching(143)

Expert replies
by sandy217 » Sun Jun 05, 2011 6:17 am
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

[spoiler]No IMO's Please..Any specific reason for eleminating D[/spoiler]
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Source: — Sentence Correction |

by sameerballani » Sun Jun 05, 2011 6:27 am
sandy217 wrote: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

[spoiler]No IMO's Please..Any specific reason for eleminating D[/spoiler]
i feel E is correct because of the usage had been
what's the OA?
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by cans » Sun Jun 05, 2011 6:38 am
IMO E
that was as early as 18th century is incorrect
If my post helped you- let me know by pushing the thanks button ;)

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Cans!!
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by itsmebharat » Sun Jun 05, 2011 7:19 am
IMO [spoiler]E

This ques is testing tenses.. had been is correct here.[/spoiler][/spoiler]
I am not an Expert, please feel free to suggest if there is an error.
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by Frankenstein » Sun Jun 05, 2011 7:31 am
sandy217 wrote: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

[spoiler]No IMO's Please..Any specific reason for eleminating D[/spoiler]
Hi,
E is definitely out because of 2 reasons. 'past perfect' is not needed. Simple past will suffice. and well established modifies 'leaching' or 'mineral extraction'?
So, it has to be either C or D. As you have asked how to eliminate D, I can assume 'C' is correct.
If I look for reasons to eliminate 'D' I can find the following:
'that was' is really necessary?
mineral extraction better than extracting mineral ?
Cheers!

Things are not what they appear to be... nor are they otherwise
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by Bhavishya » Sun Jun 05, 2011 8:10 am
Its not E mainly because leaching is something that is still there. Had been makes it a matter of past which is wrong.
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by abhi0697 » Sun Jun 05, 2011 8:17 am
IMO C

Past Perfect is only used when the sequence of events has to be made clear. In this sentence, sequence is clear by the use of "..as early as eighteenth century, but until about 25 years ago.."
In this sentence, Simple Past will do.
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by sanabk » Sun Jun 05, 2011 8:50 am
E
Till date leaching is an extraction method.
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by nafiul9090 » Mon Jun 06, 2011 9:10 pm
hello

is D incorrect because "that" is incorrectly modifies mineral whereas the issue is the process "leaching??

regards nafi
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by siddus » Tue Jun 07, 2011 1:20 am
There is a very good point made somewhere on the Manhattan forums by one of the tutors
https://www.manhattangmat.com/forums/leaching-t6199.html

In option E, the use of the perfect past tense is inappropriate because the perfect past tense must be used to denote a state that is no longer applicable. In this sentence, it is most likely that leeching is still very much in use. So there is no reason to use the perfect past tense here.

Moreover, D uses the past tense and communicates the correct meaning clearly:

Leaching, the recovery of copper from the drainage water of mines, was a well-established method of mineral extraction 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.
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by EducationAisle » Tue Jun 07, 2011 6:13 am
Past Perfect is used to depict events at a non-specific time in the past. This sentence establishes a clear time (eighteenth century) and hence, Past Perfect is not valid.

Following however, would have been correct (from Tense Perspective):

Leaching, the recovery of copper from the drainage water of mines, had been a well-established method of mineral extraction, but until about 25 years ago miners did not realize that bacteria take an active part in the process.
Ashish
MBA - ISB, GMAT - 99th Percentile
GMAT Faculty @ EducationAisle
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by siddus » Tue Jun 07, 2011 6:17 am
EducationAisle wrote:Past Perfect is used to depict events at a non-specific time in the past. This sentence establishes a clear time (eighteenth century) and hence, Past Perfect is not valid.

Following however, would have been correct (from Tense Perspective):

Leaching, the recovery of copper from the drainage water of mines, had been a well-established method of mineral extraction, but until about 25 years ago miners did not realize that bacteria take an active part in the process.
Well, the sentence with the past perfect tense is correct but the simple past would be a better choice here.
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by EducationAisle » Tue Jun 07, 2011 6:19 am
siddus wrote: Well, the sentence with the past perfect tense is correct but the simple past would be a better choice here.
No, as I mentioned, Past Perfect is in-correct in this sentence.

Edit: By the way, following would also have been correct (from Tense perspective):

Leaching, the recovery of copper from the drainage water of mines, had been a well-established method of mineral extraction since 18th century, but until about 25 years ago miners did not realize that bacteria take an active part in the process.
Last edited by EducationAisle on Tue Jun 07, 2011 6:21 am, edited 1 time in total.
Ashish
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by siddus » Tue Jun 07, 2011 6:21 am
EducationAisle wrote:
siddus wrote: Well, the sentence with the past perfect tense is correct but the simple past would be a better choice here.
No, as I mentioned, Past Perfect is in-correct in this sentence.
you said: Following however, would have been correct (from Tense Perspective). Thats the sentence I was talking about :)
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by EducationAisle » Tue Jun 07, 2011 6:25 am
siddus wrote: you said: Following however, would have been correct (from Tense Perspective). Thats the sentence I was talking about :)
Again no, in the alternative sentence that I proposed, Simple Past would not have worked, since Simple Past is almost always used with specific times.
Ashish
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