thanks gmat_perfect.

I am planning to appear for the test within 1 month, let see...
what is your plan ?

Somehow I know the rule [ but not able to apply here] -> there should be one independent clause and then only we can use Although clause

ie.
Structure should be
<independent clause> < although clause>

Now applying to same rule on C and E

E :
although the air that forms them is moving rapidly,
the resulting flow pattern, with stationary crests and troughs is known as "standing waves

C:
although the air that forms them is moving rapidly,
the resulting flow pattern, with crests and troughs that remain stationary is known as "standing waves

Now both are looking correct. It seems that I am missing something.

paes wrote:Thanks Mani,

I have already gone through Ron's explanation. But somehow it was not very clear to me.
Can you interpret the 2nd point in simple general term.
then it will be easy to implement it in other problems.

although' has to separate a CLAUSE : ok now can you find out the CLAUSE in C ?

i.e.
the structure should be :

<Athough..>, <clause>

now what is this clause in C, and how it is missing in E.

Hey Paes,

I guess what Ron meant was, sentences should be something like

Clause ALTHOUGH Clause.

In this case

with crests and troughs ( that remain stationary although the air that forms them is moving rapidly ) , is known as "standing waves
Here the words between braces modify crests and troughs
that remain stationary although the air that forms them is moving rapidly

That is a relative pronoun , so subject is crests and troughs with verb remain. Hence we have a clause (that remain stationary) + although + clause (the air that forms them is moving rapidly ).

Again this is completely my interpretation which can be completely wrong or wayward and comments are most welcome

paes wrote:thanks gmat_perfect.

I am planning to appear for the test within 1 month, let see...
what is your plan ?

Somehow I know the rule [ but not able to apply here] -> there should be one independent clause and then only we can use Although clause

ie.
Structure should be
<independent clause> < although clause>

Now applying to same rule on C and E

E :
although the air that forms them is moving rapidly,
the resulting flow pattern, with stationary crests and troughs is known as "standing waves

C:
although the air that forms them is moving rapidly,
the resulting flow pattern, with crests and troughs that remain stationary is known as "standing waves

Now both are looking correct. It seems that I am missing something.

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) crests and troughs that remain stationary although the air that forms them is moving rapidly, are
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 the air that forms them is moving rapidly, is

Yes you are missing a very important thing.

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.

You have made a mistake. See the green part and blue part are completely separate. You have mixed them.

You should work within the commas. The problem of although clause is within the commas.

You cannot take any word from the green part to solve the problem of blue part.

You MUST mind that:

1. The resulting flow pattern is known as "standing waves".-----Main sentence.
2. ------with crests and troughs that remain stationary although the air that forms them is moving rapidly---is the non-essential modifier.

If there is any problem in the non-essential modifier, that should be solved within that modifier.

You have done:

although the air that forms them is moving rapidly,
the resulting flow pattern, with stationary crests and troughs is known as "standing waves

You have violated the rule. A part of the non-essential modifier has been pushed into the main clause, and a part of the non-essential modifier has been taken away.

If the modifier were essential, you could write the sentence as:

Although the air that forms them is moving rapidly, the resulting flow pattern, with stationary crests and trough, is known as standing waves. ----Again this has lot of commas.

I think you got it.

Thanks.

wonderful work by gmat_perfect....

U rock man!!

thanks gmat_perfect.

Finally I got the point.
Every time I was missing the comma clause.

paes wrote:From OG 10 - SC#205 -

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) crests and troughs that remain stationary although the air that forms them is moving rapidly, are
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 the air that forms them is moving rapidly, is

[spoiler]Can somebody explain between C and E, which one is better and why ?[/spoiler]

Quickest approach:

2-3 split between are and is. The resulting flow pattern is known as standing waves. Eliminate A, B, and D.

The word although in C and E indicates contrast. Things that are being compared should be structured the same way. E compares stationary (adjective) to moving rapidly (verb). C compares remain stationary (verb) to moving rapidly (verb). Since the comparison in C is more parallel, eliminate E.

The correct answer is C.

Thanks Guru.
Your post has given a complete different view to crack this problem.

GMATGuruNY wrote:

paes wrote:From OG 10 - SC#205 -

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) crests and troughs that remain stationary although the air that forms them is moving rapidly, are
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 the air that forms them is moving rapidly, is

[spoiler]Can somebody explain between C and E, which one is better and why ?[/spoiler]

Quickest approach:

2-3 split between are and is. The resulting flow pattern is known as standing waves. Eliminate A, B, and D.

The word although in C and E indicates contrast. Things that are being compared should be structured the same way. E compares stationary (adjective) to moving rapidly (verb). C compares remain stationary (verb) to moving rapidly (verb). Since the comparison in C is more parallel, eliminate E.

The correct answer is C.

Yes, guru has explained in the decent way.

Guru does in the same way all the time.

Thanks guru.