1. Many teenagers undergo stress, but results of a recent study indicate that the patterns of stress that girls experience are more likely to result in depression than are those that boys experience.

A. are those that boys experience
B. those that boys experience

2. A study published in the British Medical Journal showed that women who ate nuts more than five times a week were about one third less likely to suffer from coronary heart disease than were those who ate no nuts at all.

A. than were those who ate
B. than those who ate

3. Results of a United States study published in the Annals of Internal Medicine have shown that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than women living in the Northeast and Midwest.

A. that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than women living

B. that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than are women living

In all the questions, option A is correct.
I basically want to ask why in 1 and 2 we require the use of verb "are" and "were" respectively, but in Q3, we do not require the verb "are".

Thanks.

A verb is optional, unless the comparison is unclear or could be misinterpreted without it.

Jerry likes George more than a root canal.
This is clear: Jerry has a preference between George and a root canal. No verb necessary, though it wouldn't be wrong to use one, just wordy: Jerry likes George more than he likes a root canal.

Jerry likes George more than Elaine.
This is not clear: Does Jerry have a preference between George and Elaine? Or do Jerry and Elaine differ in their feelings about George?

To clear up the confusion, you must use a verb:
(1) Jerry likes George more than he likes Elaine.
(Notice that "he" = Jerry, not George, as both are subjects of their respective verbs. Parallelism prevents a true pronoun ambiguity emergency, though the GMAT might still use Jerry's name instead of the pronoun to be clear.)

(2) Jerry likes George more than Elaine does.


Q3 is clear without a verb. There may be ambiguity in Q1 and Q2, or it's possible that a verb is just thrown in for "extra" clarity. I'll leave that for you to decide.

_________________
Emily Sledge
Instructor
ManhattanGMAT

I don't understand how Q3 is clear without a verb but Q1 and Q2 aren't.

If I leave out the verb "are" in Q1 then the sentence becomes:

Many teenagers undergo stress, but results of a recent study indicate that the patterns of stress that girls experience are more likely to result in depression than those that boys experience.

How is this unclear?

If we leave out the verb in Q3 the sentence becomes

Results of a United States study published in the Annals of Internal Medicine have shown that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than women living in the Northeast and Midwest.

If one were to argue that 1 is unclear without a verb, can't I argue that 3 might now suggest that the likelihood of women living in the South and West using supplemental hormones is greater than the likelihood of them "using women living in the Northeast and Midwest", as absurd as that may sound?

Emily basically pointed out that the verb may have been thrown in on 1 and 2 for extra clarity; I would agree and say that for the most part we are dealing with judgment calls here. The main thing to take away here is that the GMAT is not likely to force you to make this choice unless it is VERY clear that one option is correct and the other is wrong. I don’t think we have that in these questions. For the most part our strategy guide questions are designed to demonstrate a point rather than to be indicative of actual GMAT questions..

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Tim Sanders
Manhattan GMAT Instructor

My guess here is:

The reasaon why Q1 and Q2 need "are" is that the parallel structure in the sentences are more complicated---nouns with attribute clauses. Maybe that's why GMAC thinks they need "are" to clarify the parallelism,or the meaning.

Q3 is not that complicated as the parallel parts are just noun phrases.

Any instructor can give more lights on the differences between Q1,Q2 and Q3?

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One point to add in case this thread will be a little bit misleading: I checked back all the above 3 problems, actually GMAC don't make us choose between having a "are" and not having a "are" . Or in other words, having it or not doesn't appear to be a split there.

I think the author of this thread just wanna conjecture GMAC's preference.

it seems to me that Emily explained the relevant issues in this one. do you have a specific question that she didn't address?

_________________
Tim Sanders
Manhattan GMAT Instructor

It's a long post, but here is what I discern. Tutors, please help if I m wrong somewhere.
---------------------X-----------------------
Q1. Patterns of stress that girls experience ARE more likely to result in depression than ARE “patterns of stress” that boys experience


Patterns of stress that girls experience ARE more likely to result in depression than (to result in) “patterns of stress” that boys experience


Here -- ( patterns of stress ) --> Those
Option 1 makes more sense here
---------------------X-----------------------
---------------------X-----------------------
showed that women who ate nuts more than five times a week were about one third less likely to suffer from coronary heart disease than were “women” who ate no nuts at all

showed that women who ate nuts more than five times a week were about one third less likely to suffer from coronary heart disease than (to suffer from)“women” who ate no nuts at all

Here -- women --> those
Again, Option 1 makes more sense here
---------------------X-----------------------
---------------------X-----------------------
shown that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than (ARE) women living in the Northeast and Midwest.

shown that college-educated women and women living in the South and West are significantly more likely to use supplemental hormones than (to use) women living in the Northeast and Midwest.

here, we cannot use option 2, which is absurd ! Therefore we need not mention ARE explicitcly.
---------------------X-----------------------

seems okay to me!

_________________
Tim Sanders
Manhattan GMAT Instructor