A group of sudents who have begun to clean up Frederick Law Olmstead's

Wow....This really is a tricky and very good question. Here is my explanation.

A group of sudents who have begun to clean up Frederick Law Olmstead's Morning Park in New York City believes that the park needs not to be redesigned but to be returned to its former condition

Here relative phrase "A group of students who have begun to clean up" is infact referring to students.Hence plural verb form - have begun.

The intended meaning of the sentence refers to the group as a whole. In these cases,the verb shouldbe singular.

A group........believes that the park......is the correct usage.

Left with A and C.

Correct idiom is NOT X BUT Y where X and Y should be parallel.

In C, needs not to be redesigned but could , X is an infinitive. So Y should also be an infinite but not the case.

Hence ans= A.

I think we have approached this i one of the students- plural or singular verb issue from Kaplan, or MGMAT's point of view. Have we looked at it from the GMAC’s point of view? If not, here is a question from GPrep that employs this structure and indicates GMAC’s views on it.

According to two teams of paleontologists, recent fossil discoveries in Pakistan show that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos—than to any other mammals.
A. that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates—a group of hoofed mammals that today includes cows, camels, pigs, and hippos—than
B. that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates—a group of hoofed mammals that today include cows, camels, pigs, and hippos—as
C. whales, porpoises, and dolphins to be more closely related to some of the oldest known even-toed ungulates—a group of hoofed mammals that today include cows, camels, pigs, and hippos—than they are
D. whales, porpoises, and dolphins as being more closely related to some of the oldest known even-toed ungulates—a group of hoofed mammals that today includes cows, camels, pigs, and hippos—as they are
E. whales, porpoises, and dolphins as more closely related to some of the oldest known even-toed ungulates—a group of hoofed mammals that today include cows, camels, pigs, and hippos—than

The correct answer is choice A, containing ‘a group of hoofed mammals’ that today ‘includes’ cows, camels, pigs, and hippos’

Now you know what GMAC considers right.

Can we have some OG or GPrep example in which the GMAC has preferred the other choice?

I chose D. So what is the takeaway?

The number of Xs -> Always singular (number is the subject)
A number of X/ Half of X/ etc. -> Singular or Plural, it depends on the subject preceding the preposition of
A group of X -> Always singular (group is the subject)
The group of X - >Always singular (group is the subject)

Am I correct? Does english has another excpetion regarding the use of "A something of" whether is singular or singular/plural.

Thanks!

Hi marcovg,

A group is always a group, singular. Whoever, the verb "have" is not referring to the group--it's referring to the students. "A group of (students who are cleaning)..."

1) VERB
A group requires singular verb- believes
Only A and C possible
2) parallelism
Not X but Y
A is the answer

The verb "believes" is underlined, so determine its subject. Who's doing the believing? The group. Is it correct to say that the group believes? Yes. The stem sentence appears to be correct, but let's check out the other choices.

Three of the choices, (B), (D), and (E), use "believe" so eliminate. The verbs in choice (C) aren't parallel ("not to be…but could be"). This choice may also be eliminated. Choice (A) is parallel ("not to be…but to be") and is correct.

KAPLAN OFFICIAL EXPLANATION:

The subject is group, which is singular, so the main verb has to be believes. Also, the things linked by not and but have to be in parallel form: the infinitive to be redesigned has to be paired with the infinitive to be returned. The answer is (A), the original structure.

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