Sentence Correction

Question #90 from OG, 11th edition, soln on page 701

The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them;the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves".

A. ...

B. crests and troughs that remain stationary although they are formed by rapidly moving air, are

C. crests and troughs that remain stationary although the air that forms them is moving rapidly, is

D. stationary crests and troughs although the air that forms them is moving rapidly, are

E. stationary crests and troughs although they are formed by rapidly moving air, is



My answer was E.

But the OA is C.

What's wrong with E? Passive voice? I thought it was succinct and concise.

Wait a minute - I think I get it now. Is it because rapidly is an adverb and it's followed by "moving air", a adjective + noun? But adverb can modify adjectives right?

I thought I had it - ok, back to square 1. sometimes I just don't get this stuff .

stationary crests and troughs although they are formed by rapidly moving air

The problem with (e) is the "although they are formed..." part. Without "that are stationary", the although phrase just doesn't make sense in the sentence. ".. rapidly moving air" is just fine.

We want to contrast "stationary" with "rapidly moving air", (e) doesn't present that contrast clearly.

One thing that strikes me right away with the answer choices is the "are known as" vs. "is known as". Well what are known as? In this case the subject is "the resulting flow pattern", and easy way to see this is the that the main part of the underlined section is in between comma's and is extra information and the sentence can read "the resulting flow pattern....is known as. Therefore choose "is known as" rather than "are known as". The resulting flow pattern is singular. Right away you have gotten rid of answer choices A, B & D.

Now what differs between C and E. "Although the air that forms...." and "although they are formed by". What is "they" refering to? Is they refering to stationary crests and troughs (as in E) or the resulting flow pattern. C clears up any ambiguities to what they refers to, and makes the sentence clearer, than E. C is the best choice.

Honestly all the answer choices suck but as I was told by Manhattan GMAT instructors "you have to choose the cream of the crap" in SC.

Good Luck
Kaunteya

Kaunteya1 wrote:One thing that strikes me right away with the answer choices is the "are known as" vs. "is known as". Well what are known as? In this case the subject is "the resulting flow pattern", and easy way to see this is the that the main part of the underlined section is in between comma's and is extra information and the sentence can read "the resulting flow pattern....is known as. Therefore choose "is known as" rather than "are known as". The resulting flow pattern is singular. Right away you have gotten rid of answer choices A, B & D.

Now what differs between C and E. "Although the air that forms...." and "although they are formed by". What is "they" refering to? Is they refering to stationary crests and troughs (as in E) or the resulting flow pattern. C clears up any ambiguities to what they refers to, and makes the sentence clearer, than E. C is the best choice.

Honestly all the answer choices suck but as I was told by Manhattan GMAT instructors "you have to choose the cream of the crap" in SC.

Good Luck
Kaunteya

I strongly disagree that all the answers suck. I also disagree that we need to choose the best of a bad bunch in SC.

(c) is a perfectly fine answer. The "them" in (c) (which is pretty much equivalent to the "they" in (e), by the way) clearly refers to BOTH the crests and troughs.

as mentioned by Kaunteya (a), (b) and (d) can be gotten rid of.

Now for (c) and (e) lets compare them.

(E) -- There is redundancy.

The sentence can be written as

1. stationary crests and troughs although formed by rapidly moving air or 2. stationary crests and troughs that are formed by rapidly moving air.

but not "stationary crests and troughs although they are formed by rapidly moving air, is".

hence the best answer choise in (c).

This analysis is completely based on my experience and it is not thru any book. So i donot vouch by it

I also chosed E.

before although clause, there must be a clause,

do you have sentence correction bible, pls email to me, I am in vietnam, a country which do not use english, so I can not buy the book, Please, help

boston_mba wrote:Question #90 from OG, 11th edition, soln on page 701

The peaks of a mountain range, acting like rocks in a streambed, produce ripples in the air flowing over them;the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves".

A. ...

B. crests and troughs that remain stationary although they are formed by rapidly moving air, are

C. crests and troughs that remain stationary although the air that forms them is moving rapidly, is

D. stationary crests and troughs although the air that forms them is moving rapidly, are

E. stationary crests and troughs although they are formed by rapidly moving air, is



My answer was E.

But the OA is C.

What's wrong with E? Passive voice? I thought it was succinct and concise.

Wait a minute - I think I get it now. Is it because rapidly is an adverb and it's followed by "moving air", a adjective + noun? But adverb can modify adjectives right?

I thought I had it - ok, back to square 1. sometimes I just don't get this stuff .

Subject-Verb agreement.

So we can easily eliminate A, B, and D.

C or E?

"crests and troughs that remain stationary" or "stationary crests and troughs "


There is difference between " stationary things" and "things that remains stationary..."

although introduces sub-ordinate clause. But in E there is no main clause for "although they are formed by rapidly moving ". (If my understanding is incorrect, please do correct it)

C is the right answer.

I have a simple questions.
Why does "them" in the second clause cannot refer to "ripples" in the first clause ?

manihar.sidharth wrote:I have a simple questions.
Why does "them" in the second clause cannot refer to "ripples" in the first clause ?

I am thinking that you are referring to "them" in the underlined portion. "ripples" actually appears "before" the semicolon.

So, I feel "them" cannot refer to "ripples". I somehow feel that a pronoun after the semicolon cannot refer to the noun before the semicolon. Can an expert verify this.

manihar.sidharth wrote:I have a simple questions.
Why does "them" in the second clause cannot refer to "ripples" in the first clause ?

C: with CRESTS AND TROUGHS that remain stationary although THE AIR THAT FORMS THEM is moving rapidly
This modifier is clearly expressing a contrast between CRESTS AND TROUGHS and THE AIR THAT FORMS THEM, with them serving to refer to crests and troughs.
No reasonable reader would construe that them serves to refer to ripples, a noun in the preceding clause.

I somehow feel that a pronoun after the semicolon cannot refer to the noun before the semicolon. Can an expert verify this.

A pronoun after a semi-colon can serve to refer to a noun preceding the semi-colon, but this construction is rare.
SC105 in the OG13:
Marconi conceived of the RADIO as a tool for private conversation; instead, IT has become precisely the opposite.
Here, IT (a pronoun after the semi-colon) serves to refer to RADIO (a noun preceding the semi-colon).