synthetic growth hormone and Lina's sunbird

[gmat.2008]

plz explain me the following two questions:


Before scientists learned how to make a synthetic growth hormone, removing it painstakingly in small amounts from the pituitary glands of human cadavers.

(A) scientists learned how to make a synthetic growth hormone, removing it painstakingly
(B) scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly
(C) scientists learned how to synthesize the growth hormone, it had to be painstakingly removed
(D) learning how to make a synthetic growth hormone, scientists had to remove it painstakingly
(E) learning how to synthesize the growth hormone, it had to be painstakingly removed by scientists

ans given is C.... but i think its D...



First discovered more than 30 years ago, Lina's sunbird, a four-and-a-half-inch animal found in the Phillippines and that resembles a hummingbird, has simmering metallic colors on its head; a brilliant orange patch, bordered with red tufts, in the center of its breast; and a red eye.

(A) found in the Phillippines and that resembles

(B) found in the Phillippines and that, resembling

(C) found in the Phillippines and resembling

(D) that is found in the Phillippines and it resembles

(E) that is found in the Phillippines and that, resembling

OA-C . even i chose C because its the shortest but i want to know the basics behind this.
[/img][/list][/quote]

[piyush_nitt]

plz explain me the following two questions:


Before scientists learned how to make a synthetic growth hormone, removing it painstakingly in small amounts from the pituitary glands of human cadavers.

(A) scientists learned how to make a synthetic growth hormone, removing it painstakingly
(B) scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly
(C) scientists learned how to synthesize the growth hormone, it had to be painstakingly removed
(D) learning how to make a synthetic growth hormone, scientists had to remove it painstakingly
(E) learning how to synthesize the growth hormone, it had to be painstakingly removed by scientists

ans given is C.... but i think its D...

need past tense learned instead of learning .

learned , had removed - events occured in the past . before scientist learned ...hormones had to be removed -- correct usage


First discovered more than 30 years ago, Lina's sunbird, a four-and-a-half-inch animal found in the Phillippines and that resembles a hummingbird, has simmering metallic colors on its head; a brilliant orange patch, bordered with red tufts, in the center of its breast; and a red eye.

(A) found in the Phillippines and that resembles

(B) found in the Phillippines and that, resembling

(C) found in the Phillippines and resembling

(D) that is found in the Phillippines and it resembles

(E) that is found in the Phillippines and that, resembling

OA-C . even i chose C because its the shortest but i want to know the basics behind this.

The reason I chose C

that always introduces the restrictive clause. and here that is the part of non - restrictive clause[/img][/list]

[/quote]

[Bidisha800]

You are just starting so I think you should pick up a grammar book and read cover to cover .... It may sound boring but it can pay hefty dividends ...


Before scientists learned how to synthesize the growth hormone, it had to be painstakingly removed

Two actions are compared and sequence of events are stated. "had" is used to describe the event that completed before the current event - scientists learned (use of simple past)


The second question is dealing with participle modifiers. There are chapters dedicated in grammar books on Participle, Infinitives and Gerunds.

[greenwich]

plz explain me the following two questions:


Before scientists learned how to make a synthetic growth hormone, removing it painstakingly in small amounts from the pituitary glands of human cadavers.

(A) scientists learned how to make a synthetic growth hormone, removing it painstakingly
(B) scientists had learned about making a synthetic growth hormone, they had to remove it painstakingly
(C) scientists learned how to synthesize the growth hormone, it had to be painstakingly removed
(D) learning how to make a synthetic growth hormone, scientists had to remove it painstakingly
(E) learning how to synthesize the growth hormone, it had to be painstakingly removed by scientists

ans given is C.... but i think its D...



What's wrong with A?

[Isaac@EconomistGMAT]

Going over all the answer choices:

A is wrong because it is not a full sentence. It is a fragment. We know this because the clause which begins with 'Before', needs a second half (in this case after the comma) and that second half or second clause should also have its own subject and verb, which it does not.

Example: Before I went to sleep, brushing my teeth.

Correct: Before I went to sleep, I had brushed my teeth.

This does not work; what occurred before going to sleep? What action? Words such as 'before' can start a clause and when they do, you need the other clause present as well.

So we can get rid of D and E right away. Now you have another hint, namely the word 'before'. When used to describe a past action you should also check out whether there is another past action in the sentence. This would indicate that there should be a Past Perfect or Past Perfect like Verb. The Verb that happened first should be in the Past Perfect while the 'later' action should be in the Past Simple. Therefore eliminate B because what the scientists 'learned' came after the first action 'removed' not before it and should not be in the Past Perfect, but the Past Simple.

This leaves us with answer choice C, which although containing the Passive (not preferable), it is still the best answer choice left.

As for the second question, do not add a clause when you can say things in a more concise manner without the use of a clause. In this case, 'resembling' is a participle which works as a modifier, describing the songbird. The 'and' that comes between 'found' and '...resembles' requires a Parallelism and since 'found' is a past participle/non conjugated verb , and properly and concisely describes the songbird, the 'resembles' should also be a non conjugated verb that works as a modifier.

Oftentimes too, you can get rid of the 'that' and the Verb 'to be that comes before the Past Participle (to form the passive) altogether to make the sentence more concise. (see the difference between the right answer and answer choices D and E)

Example: We saw the toy that was bought in the store --> We saw the toy bought in the store.

[GMATMadeEasy]

(D) learning how to make a synthetic growth hormone, scientists had to remove it painstakingly

Choice D has actor as scientist , why it will be wrong ?

[Isaac@EconomistGMAT]

Actually, a good question.

Which answer choice is more concise though?

How to synthesize the growth hormone
versus
how to make a synthetic growth hormone

Also notice that a meaning change can be construed in this case when looking at the article 'the' (specific growth hormone in answer c) versus 'a' general growth hormone. Sometime 'a' and 'the' can both be used to denote something general but in this case it may be explained as a slight meaning change (of they want to be mean about it. The main thing is that C is less wordy and therefore less awkward.