Unlike frogs that metamorphose from tadpoles into adults

[deadpig1987hahaha]

Unlike frogs that metamorphose from tadpoles into adults within a one-year period, it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

(A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are
(B) it takes the mountain yellow-legged frog of the Sierra Nevada three to four years until it reaches adulthood, and therefore it is
(C) in the Sierra Nevada, mountain yellow-legged tree frogs take three to four years to reach adulthood, thus being
(D) mountain yellow-legged frogs of the Sierra Nevada take three to four years until they reach adulthood, thus
(E) mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, and so they are

the OA is E
But aren't and and so both conj? I never saw people putting these 2 words together before.
and I think I've found the original source of this sentence in NEW York Time
http://www.nytimes.com/2000/11/28/scien ... wanted=all
"Also, unlike many other frogs that metamorphose from tadpoles to adults in one year, the high-elevation frogs take three to four years to reach adulthood, so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter. "

it doesn't have and before so in the original sentence.

Can anyone explain this to me?

Thanks a lot

[RonPurewal]

But aren't and and so both conj? I never saw people putting these 2 words together before.

this is where we step in with the following astonishingly simple, but 100% reliable, rule:

on official problems, CORRECT ANSWERS ARE CORRECT.

see here:
http://www.manhattangmat.com/blog/index ... -the-gmat/

the only way you can approach these things effectively is to say
"oh, ok, i didn't know you could do that"
and then add the example to your mental repository.

since the question is official, it's a complete waste of your time to continue doubting it after you've verified that it's the OA.

[rohit21384]

Hi
is d wrong because it is changing the meaning:
wording in d means that it takes 3-4 years to metamorphose until they reach adulthood, then they might take different time (differnent from 3 to 4 years) to metmorphose.

[RonPurewal]

Hi
is d wrong because it is changing the meaning:
wording in d means that it takes 3-4 years to metamorphose until they reach adulthood, then they might take different time (differnent from 3 to 4 years) to metmorphose.

nah, not really. there are 2 things wrong with that choice, though.

* unidiomatic use of "until".
you can't say "you'll take X amount of time UNTIL..."
UNTIL is used after a description of an action: i will run until i become exhausted.
the correct idiomatic expression is "you'll take X amount of time to VERB," as used in the correct choice.

* the modifier doesn't make sense. since "(thus) restricted" functions as an adjective, this modifier (like all other adjectival modifiers) tags onto the preceding noun. therefore, this sentence is saying that adulthood is confined to deeper bodies of water, a nonsense statement.

[agha79]

Hi Ron -
In "E" the correct answer choice why "...adulthood, and" is correct? I have seen on the form in some other questions that if we don’t have a list of items we can’t use " , and". Can you please help me understand when this construction is acceptable?
I eliminated "E" right away because of this construction
Regards,

[NIKESH_PAHUJA]

Hi Ron -
In "E" the correct answer choice why "...adulthood, and" is correct? I have seen on the form in some other questions that if we don’t have a list of items we can’t use " , and". Can you please help me understand when this construction is acceptable?
I eliminated "E" right away because of this construction
Regards,

@Agha79,

And is a conjunction and is used to connect grammatically coordinate words, phrases, or clauses

e.g

He felt sick and decided to lie down for a while
He read for an hour and went to bed
They invited every Tom, Dick, and Harry to the party

List of items needs 'and' , as you said, because it includes grammatically coordinated words.

Caution --- > do not use 'and' with subordinate clauses.

Although, while etc....are subordinating conjunctions, and are used to connect subordinating clauses.

[RonPurewal]

Hi Ron -
In "E" the correct answer choice why "...adulthood, and" is correct? I have seen on the form in some other questions that if we don’t have a list of items we can’t use " , and". Can you please help me understand when this construction is acceptable?
I eliminated "E" right away because of this construction
Regards,

hi -

if you use "and" to connect two independent clauses (i.e., two constructions each of which is a complete sentence on its own), then it is normally preceded by a comma.

this is not a 100% rule; you'll occasionally see two independent clauses separated by just "and", without a comma. (usually, this only happens if the clauses are really short.) but it's the usual convention.

[zhongshanlh]

Ron,
i have a question about option C.

specifically, i would like to know if the use of ", thus being restricted..." is correct?

IMO,i think the this construction is properly used because it meets the requirements when we use a COMMA verbING construction,so please help and thank you so much.

[tim]

this construction is certainly suspect, but i wouldn't rule out C on those grounds alone. fortunately, there are other more clear reasons to get rid of C..

[krishnan.anju1987]

Thus being wrong somehow sounds wrong to me but I just can't put the finger on why. Although I understand the other reasons for eliminating this option, I would be glad to find out whether there is some specific reason we can use that expression?

[RonPurewal]

Thus being wrong somehow sounds wrong to me but I just can't put the finger on why. Although I understand the other reasons for eliminating this option, I would be glad to find out whether there is some specific reason we can use that expression?

in general, modifiers that start with "being" are sub-optimal.

however, you should be able to kill (c) pretty quickly on the grounds that it doesn't start with mountain yellow-legged frogs (and thus finishes the unlike... comparison incorrectly).

[mcmebk]

Hi
is d wrong because it is changing the meaning:
wording in d means that it takes 3-4 years to metamorphose until they reach adulthood, then they might take different time (differnent from 3 to 4 years) to metmorphose.

nah, not really. there are 2 things wrong with that choice, though.

* unidiomatic use of "until".
you can't say "you'll take X amount of time UNTIL..."
UNTIL is used after a description of an action: i will run until i become exhausted.
the correct idiomatic expression is "you'll take X amount of time to VERB," as used in the correct choice.

* the modifier doesn't make sense. since "(thus) restricted" functions as an adjective, this modifier (like all other adjectival modifiers) tags onto the preceding noun. therefore, this sentence is saying that adulthood is confined to deeper bodies of water, a nonsense statement.

Hi Ron

I thought you taught us comma+verb-ed modifies the subject of preceding clause, i.e

He took a nap, tired of working.

Can we look at option from a different perspective - I feel the comma+verb-ed part normally explains, or give extra information about the act in the preceding clause, however, in this sentence, if "Restricted..." does modify the subject frogs, there is no intimate relationship between them whatsoever, and is thus wrong.

Could you please correct me if my thinking is wrong?

Thank you Ron.

[mcmebk]

Hi Ron/Stacy

One myth I haven't been able to resolve myself, is about the usage of comma+verb-ed, as described in this question.

I understand when it is used as an open modifier, it modifies the following subject:

Gone with the wind, the balloon disappears - The balloon is gone with the wind;

When used without comma, it modifies the preceding noun:

I see the cat hidden under the bed - The cat is hidden under the bed;

While in the usage of "comma+Verb-ed modifier", I sincerely don't know which noun it is supposed to modify:

I see the cat, hidden under the bed - In this case, do we decide the modified noun using logic sense "It is the cat, not I, is hidden under the bed", or is it for certain modify the noun it immediately follows "the cat", or the subject in the preceding clause "I"?

Thank you so much for your help.

[jlucero]

Hi Ron/Stacy

One myth I haven't been able to resolve myself, is about the usage of comma+verb-ed, as described in this question.

I understand when it is used as an open modifier, it modifies the following subject:

Gone with the wind, the balloon disappears - The balloon is gone with the wind;

When used without comma, it modifies the preceding noun:

I see the cat hidden under the bed - The cat is hidden under the bed;

While in the usage of "comma+Verb-ed modifier", I sincerely don't know which noun it is supposed to modify:

I see the cat, hidden under the bed - In this case, do we decide the modified noun using logic sense "It is the cat, not I, is hidden under the bed", or is it for certain modify the noun it immediately follows "the cat", or the subject in the preceding clause "I"?

Thank you so much for your help.

Rather than learn rules (which tend to have exceptions) for all instances, look for instances in which the meaning is ambiguous and eliminate those answers. In your example, you would not be hidden under, but rather you would be hiding under the bed. So no matter where the "hidden under the bed" goes, it would be describing the cat.

Hidden under the bed, I see the cat. (hidden cat)
I see the cat, hidden under the bed. (hidden cat)

When a phrase could modify either the subject or object, put it closer to the part you want to modify.

Hiding under the bed, I see the cat. (I am hiding)
I see the cat hiding under the bed. (the cat is hiding)
I see the cat, hiding under the bed. (slightly ambiguous- avoid this option IF it is the only/last split available to you)

As always, the name of the game is finding the one, clear, unambiguous sentence. The GMAT will sometimes use commas for before these verb-ing phrases and sometimes does not. But the correct answer choice should still be clear in its meaning.

Finally, while this is great that you are learning this, I'd venture a guess that many of our instructors would use punctuation as an absolute last resort for picking SC. So don't feel as though you need to know every last split in every answer choice to do well on this. Focus on the bigger, more egregious errors.

[boncourage]

Hi Ron, in Prep Exam Pack 1, answer choice E has been changed as follows:

E. mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, with the result that they are

As I see it, this construction is very similar to another prep SC:
The honeybee’s stinger is heavily barbed and stays where it is inserted, with the result that the act of stinging causes the bee to sustain a fatal injury.

Both of them state an fact and then the consequence related to the former part.

Before studying these two SC, I thought "with the result that... " is kind of redundant to express a result...

Pls. correct me if i'm wrong. Appreciate any explanations on the usage of "with the result that...". Thank you!