Grammar question about gerunds and verb agreement?

Question

This question was in the Writing section of a practice SAT from the College Board "Official SAT Book."

A_Introducing_ new ideas and replacing B_old ones_ C_is_ always a highly controversial matter, D_especially when_ there is already tension between an older and a younger generation. E_No error_

I put (C) but the answer is (E) No error. I thought that since there are two gerunds, the verb should be plural.

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From http://highered.mcgraw-hill.com/site...99/index.html:

GERUNDS AS SUBJECTS

A gerund is a noun that ends in -ing and that stands for an activity: running, writing, studying, working, reading, understanding. Deal with gerunds as you would other nouns.

Donating food at our church helps [not help] the needy.
Swimming and running are [not is] my favorite exercises.
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However, what makes the use of gerunds in this sentence different? Is there a delineating line as to why in some cases the singular form is used and other times, plural? Thanks.

Answer 1

Yes but in this case. they are asking for one thing - "ideas" whether they are old ones or new ones, they are still only one thing - "ideas"

Also, when they are asking about either one thing or another but not both, they would not be pluralized.

If you were to say: "either swimming or running is my favorite exercise but not both." this would be correct. Or you could say "Neither swimming nor running is my favorite exercise."

Answer 2

Toughie. I can see what you are saying. However, I think most people would interpret the phrase as one whole phrase:

[Introducing new ideas and replacing old ones] is always a highly controversial matter.

This is strengthened, I suppose, by the fact that the subject complement/predicate nominative is "matter", a singular noun.

Answer 3

"Introducing new ideas and replacing old ones" can be thought of as one activity. If you called them highly controversial matters, rather than a highly controversial matter, you would be treating them as though they are independent things. Similarly swimming and running are two separate exercises, but one might perhaps say "Running and jumping is the best way to clear that fence."