GMAT Prep II: Unlike crested wheatgrass

[TP]

I actually chose C as the answer. The correct answer is A. Can someone help
me understand as to why? Did C change the meaning?

thanks.

[RA]

Option "A" correctly compares 2 types of wheatgrasses whereas option "C" compares a type of wheatgrass with a root system.

[vineetagrwal]

Why isnt the answer A? Is the use of which better than gerund?

[Suyash]

Tha answer is A because the comparison is correct in a and b.So eliminate c,d,e.Moreover "their"is ambiguous in b.Hence go with a.

[jwinawer]

Tha answer is A because the comparison is correct in a and b.So eliminate c,d,e.Moreover "their"is ambiguous in b.Hence go with a.

Nice work, Suyash. In addition, "do not grow" in A is better than "without growing" in B. But the key idea, as noted above, is that C D and E have faulty comparisons.

[Guest]

Unlike crested wheatgrass, an alien species from Siberia that forms only shallow roots and produces tall above-ground shoots, native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very tall.

(A) native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very
(B) native North American grasses develop an extensive root system, which allows for their greater enrichment of the soil, but without growing to be that
(C) the root system of native North American grasses is extensive, allowing for greater enrichment of the soil, but they do not grow to be very
(D) the root system of native North American grasses is more extensive, allowing for the greater enrichment of the soil, but these grasses do not grow to be very
(E) the extensiveness of the root system of native North American grasses allows for their greater enrichment of the soil, but they do not grow to be that

1,
In B, I think "their" can only refer native North American grasses ?
2,
In A, "allowing for greater enrichment of the soil" modify
the entire clause of "native North American grasses develop an extensive root system"
or modify the "an extensive root system" ?

Thanks in advance.

[RonPurewal]

In B, I think "their" can only refer native North American grasses ?

correct.

the use of the pronoun here is problematic, though, because the exact meaning of the original sentence is more general: it's the development of the extensive root system, in general, that allows for the enrichment of the soil.
to say that the grasses themselves allow for that enrichment isn't quite accurate.

2,
In A, "allowing for greater enrichment of the soil" modify
the entire clause of "native North American grasses develop an extensive root system"
or modify the "an extensive root system" ?

the former.

when you have an -ING MODIFIER PRECEDED BY A COMMA, it's an adverbial modifier that modifies the entire preceding clause.
the comma is crucial here, by the way; if it's not there, than the -ing modifier is actually an adjectival modifier that modifies the preceding noun.


Thanks in advance.

[manish1sinha]

Unlike crested wheatgrass, an alien species from Siberia that forms only shallow roots and produces tall above-ground shoots,native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very tall.

Could someone please explain how the clause after "comma but" independent In the correct option A.
I am not questioning the correct option but trying to understand the concept.

Thanks in advance. :)

[mourinhogmat2]

Unlike crested wheatgrass, an alien species from Siberia that forms only shallow roots and produces tall above-ground shoots, native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very tall.

(A) native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very
(B) native North American grasses develop an extensive root system, which allows for their greater enrichment of the soil, but without growing to be that
(C) the root system of native North American grasses is extensive, allowing for greater enrichment of the soil, but they do not grow to be very
(D) the root system of native North American grasses is more extensive, allowing for the greater enrichment of the soil, but these grasses do not grow to be very
(E) the extensiveness of the root system of native North American grasses allows for their greater enrichment of the soil, but they do not grow to be that

We are comparing two different grasses. So, that rules out C, D and E.
The root is supposed to enrich the soil not the grasses. But the root has an article AN in front of it making it singular. So, it cant refer to the root?

So, A.

[RonPurewal]

Unlike crested wheatgrass, an alien species from Siberia that forms only shallow roots and produces tall above-ground shoots,native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very tall.

Could someone please explain how the clause after "comma but" independent In the correct option A.
I am not questioning the correct option but trying to understand the concept.

Thanks in advance. :)

it's not an independent clause.

here's the way this breaks down:

* this is NOT a construction of the form "independent clause + comma + BUT + independent clause".

* the comma preceding "but" actually belongs to the immediately preceding modifier, which i've highlighted in blue here:
native North American grasses develop an extensive root system, allowing for greater enrichment of the soil, but do not grow to be very tall

* if we remove that modifier, here's the remaining sentence:
native North American grasses develop an extensive root system but do not grow to be very tall

* note the good parallelism in that remaining sentence:
develop...
BUT
do not grow...

there you go.

[alicezyk]

Hi Instructor. I know this is an old question, but I just started preparing for GMAT.
So here is my question.

Subject+Verb+Object, but S+V+O

I thought this should be the correct structure.
But here, in this question, there is no subject after but.
Isn't it a problem?

Thanks!
Alice

[aliassad]

But is a one word parallel marker so you do not need to replicate
everything on each side

For example

"He is not only educated but also smart"

Here you do not need the subject he after but.

Similarly

"and" is another one word parallel marker

"I have a black car and a blue bike"

I need not be repeated here.


Ali Asad

[RonPurewal]

But is a one word parallel marker so you do not need to replicate
everything on each side

For example

"He is not only educated but also smart"

Here you do not need the subject he after but.

Similarly

"and" is another one word parallel marker

"I have a black car and a blue bike"

I need not be repeated here.


Ali Asad

precisely.
and very well explained!

[alicezyk]

But is a one word parallel marker so you do not need to replicate
everything on each side

For example

"He is not only educated but also smart"

Here you do not need the subject he after but.

Similarly

"and" is another one word parallel marker

"I have a black car and a blue bike"

I need not be repeated here.


Ali Asad

precisely.
and very well explained!

Hi Ron. My problem is not about whether I need to have the same structure, but about the " COMMA".
Since my question it S+v+O, but S+V+O
IF It's S+V+O BUT v+O, there shouldn't be a comma, isn't it?
So S+V+O, But V+O should be incorrect?
I just remembered the rule from MGMAT SC, saying that for 2 clauses connected by and, there should be a comma after and.
S+V+O, AND S+V+O

So I thought it works the same for but...
I am confused.
So this sentence ' I like watching TV, and listening to music' is correct ?
HOW ABOUT THIS, ' I study hard, but get low score'?
Plz clarify.
Thanks!

[jlucero]

The comma isn't there to offset the V-O but to offset the phrase "allowing for greater enrichment of the soil."

If you took that phrase out, the sentence would be:

Native North American grasses develop an extensive root system but do not grow to be very tall.

No commas, so your two examples should also not include commas.