The peaks of a mountain range

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 447
Joined: Sun Apr 19, 2009 9:08 pm
Location: Kolkata,India
Thanked: 7 times
GMAT Score:670

The peaks of a mountain range

by uptowngirl92 » Mon Jul 06, 2009 6:50 pm
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 toughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."

A) crests and toughs that remain stationary although the air that forms them is moving rapidly, are
B) crests and toughs that remain stationary although they are formed by rapidly moving air, are
C)crests and toughs that remain stationary although the air that forms them is moving rapidly, is
D)stationary crests and toughs although the air that forms them is moving rapidly, are
E)stationary crests and toughs although they are formed by rapidly moving air, is.

completly lost on the OG explanation.Can anybody throw some light in detail?
Source: — Sentence Correction |

User avatar
Master | Next Rank: 500 Posts
Posts: 435
Joined: Sat Sep 27, 2008 2:02 pm
Location: San Jose, CA
Thanked: 43 times
Followed by:1 members
GMAT Score:720

by dumb.doofus » Mon Jul 06, 2009 7:02 pm
3:2 split between "is" and "are"..

Since we are talking about the resulting flow pattern and that's singular, we should use "is", i.e. the resulting flow pattern.... "is" known as

so u can strike out A, B and D

Strike out E as it is passive (formed by).. we are left with C
One love, one blood, one life. You got to do what you should.
https://dreambigdreamhigh.blocked/
https://gmattoughies.blocked/

User avatar
MBA Admissions Consultant
Posts: 1090
Joined: Wed May 27, 2009 4:06 am
Thanked: 175 times
Followed by:68 members
GMAT Score:750

by Bryant@VeritasPrep » Mon Jul 06, 2009 7:03 pm
We know the answer must be C or E since the subject is singular ("pattern") and therefore requires "is" instead of "are." Of the two choices which have "is," the better answer seems to be "C" because it is clearer with parallell structure for the two subjects.
Bryant Michaels
MBA Admissions Consultant


Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options

User avatar
MBA Student
Posts: 1194
Joined: Sat Aug 16, 2008 9:42 pm
Location: Paris, France
Thanked: 71 times
Followed by:17 members
GMAT Score:710

by gmat740 » Mon Jul 06, 2009 7:04 pm
Original Sentence :
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 toughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."
This makes everything clear I suppose.
"the air"=> singular
" the resulting flow pattern" => singular

Only C has this combination
C)crests and toughs that remain stationary although the air that forms them is moving rapidly, is

• Page 1 of 1