NOUN + NOUN MODIFIER VS. VERB-ING MODIFIER

As discussed in our previous article named “Noun + Noun Modifiers: The most “versatile” modifiers” (modification-by-noun-noun-modifiers-137292.html#p1112971), these modifiers can modify the preceding noun, a noun in the middle of the sentence, or the entire preceding clause. They share a commonality with Verb-ing modifiers preceded by a comma in that both these modifiers modify the preceding clause. They also act like Verb-ed modifiers when they modify the preceding noun.

Despite these similarities, Noun + Noun Modifiers remain distinct from Verb-ing and Verb-ed modifiers in their function and structure both. Let’s delve into these dissimilarities between Noun + Noun Modifiers and other modifiers.
So now we know that there are two modifiers that can refer to entire preceding clause:
1. Noun + Noun Modifiers
2. Verb-ing modifiers preceded by a comma.



Even though these modifiers perform similar job of modifying the preceding clause, they are quite different in the way they perform their jobs.
The difference between these two kinds of modifiers is that when the verb-ing modifier preceded by a comma modifies the preceding clause, it presents either additional information or the result of the preceding clause by associating itself with the subject and the verb of the preceding clause. The verb-ing modifier preceded by a comma has to modify the subject and the verb together.

However, the noun + noun modifier has no such restriction. It can simply modify just about any aspect of the preceding clause, without being restricted to modify the subject and the verb. A noun + noun modifier can zoom into any entity in the preceding clause to modify it.
Another thing to notice here is that, when noun + noun modifier modifies the entire preceding clause, then it can present any kind of additional information about the preceding clause. This information can be the result, the reason, the HOW aspect, just about any information about the modified clause.
 

OFFICIAL EXAMPLE: GMAT Prep



So let’s first understand the meaning of the sentence. The sentence says that one automobile manufacturer has announced plans to increase the average fuel efficiency of its SUVs by 25% over the next five years. This increase will amount to roughly five miles per gallon and will represent the first significant change in the fuel efficiency of any class of passenger vehicle in almost 20 years.

Now the way this sentence uses the verb-ing modifiers “amounting” and “resulting”, both preceded by comma, these modifiers seems to present the result of the preceding clause “One automobile manufacturer has announced plans…”. Here, both the modifiers are referring to the subject and the verb of the preceding main clause. Logically, this does not make sense because announcement of plans cannot amount to five miles per gallon. The act of mere announcement cannot even represent first significant change. Hence, the use of verb-ing modifiers is incorrect in this sentence.



Now let’s analyze the sentence with correct answer choice D:



In this sentence, verb-ing modifiers “amounting…” and “representing…” have replaced with noun + noun modifiers “an increase that would amount to…” and “(an increase) that would represent…”. Here,

an increase = noun
“that would amount…” and “that would represent…” = noun modifiers (relative pronoun clauses)

By converting the verb-ing modifiers into noun + noun modifier, we are able to rectify the modification error easily because now, unlike the verb-ing modifiers, the noun + noun modifier need not modify the subject and the verb of the preceding clause. It can easily zoon into “increase” to present more information about this aspect of the preceding clause. This is the beauty of such modifiers.

Hope this helps.
Thanks.
Shraddha