Manhattan Prep Instructor
Joined: 22 Sep 2010
Posts: 167
Schools:MBA, Thunderbird School of Global Management / BA, Wesleyan University
Re: The early inhabitants of the Nile Valley used primitive
[#permalink]
15 Nov 2010, 07:41
This is a great opportunity to talk about "noun modifiers" and "adverbial modifiers."
A noun modifier typically starts with a comma and then a relative pronoun such as "which, who, that". In contrast, an adverbial modifier often starts with a comma and then a past participle (ending in -ed or -ing).
Noun modifiers (as seen as in A and B above):
Noun modifiers (i.e. modifiers that modify nouns) must TOUCH the word they are modifying.
It doesn't matter whether they come before or after the noun, but they must touch it. If the noun modifier doesn't touch the noun it is trying to modify, that answer choice is grammatically incorrect.
Here are a few examples:
"I read the book, which had a green cover." --> Correct. "Which had a green cover" modifies "the book" so they need to touch.
"I read the book you gave me, which had a green cover." --> Incorrect. "Which had a green cover" modifiers "me" in this example.
"A very nice man, my uncle gave $1,000 to charity yesterday." --> Correct. Although this will sound a little too Yoda-like for many people, the modifiers "A very nice man" correctly modifiers "my uncle."
"A very nice man, yesterday my uncle gave $1,000 to charity." -->Incorrect. Here, "yesterday" is "a very nice man."
Adverbial modifiers, on the other hand, do not need to touch the verb or clause they are modifying. Example:
"I ran to the house, swinging my arms" --> The modifier "swinging my arms" is an adverbial modifier because it is modifying the way I was running (i.e. it is modifying the verb "ran"). Here's a good clue that you're looking at an adverbial modifier: it starts with a past participle such as "swinging" or "considered" or "wondering". Notice how the -ing and -ed endings give this away.
Here's the point: Your first question about modifiers should be "what is it trying to modify?" If it's modifying a verb, phrase, or clause, then it's an adverbial modifier. If it's modifying a single noun, then it's a noun modifier. (Often, a noun modifier on the GMAT will mistakenly modify the wrong thing. For example: "The house where my mother lives, which is green, has two bedrooms." Here, "which is green" does not touch the noun "house." As a result, this example is incorrect.)
Once you've narrowed it down to D,C, and E using this clear grammatical rule, you can follow the logic listed by others in this thread as to how to choose a final answer.
Good luck!
Brett