If Charles had spent half as much time attending his classes as he did

The word "attending" doesn't just modify the noun "time". In fact, it modifies the entire preceding clause. The -ing modifier tells us how Charles should have spent his time.

This is a little easier to see if we get rid of the conditional "if" for a moment: "Charles spent a lot of time attending classes." How did Charles spend a lot of time? Attending classes.

For more on -ing modifiers, check out this post.

I hope this helps!
_________________

it is simple to go to choice A, because had done is need and spent require doing, not to do.

I want to make a point here

in choice A, why "he did" . use of did is correct or not.

this is conditional in the past. if some thing had happened in the past, a thing would have done in the past. "as he did" in choice A is not conditional. "as he did" is a fact. this fact happen in the past too. but this fact can happen at present

if I had learned gmat as I do today, I would have succeeded last year.

this is also correct.

what I learn from this section is that conditional had done can go with "as he did/do".

this question offer a special case in which had done go with did. a condition in the past gose with a fact in the past. this is realy interesting

"had done " can go with "would do" though "would have done" need "had done"

if you had learn gmat , you would succeed today

if in the past you did some thing, at present you will have something. this case is logical. so, do not remember that "had done" always go with "would have done"." had done "can go with "would have done "or "would do. "

I think the answer should be A.

PROCESS OF ELIMINATION -

The use of would indicates the possibility of him being a good student. 'Were' is not needed here. C & D are out.

The use of should is wrong here because we are not recommending anything and we're only discussing an alternate course of action and it's consequences. E is out.

The use of infinitives was incorrect and sounds awkward. B is out. (Would like a better explanation.)

Posted from my mobile device

The non-underlined portion of the sentence says - "he would have been a good student." This means the tense of the subject compalin and attend should be past tense. So, option C, D and E are out. Out of A and B, A seems more correct, to attend and to complain looks awkward.
IMO, (A)

Other than awkwardness as mentioned in replies , any other reason to eliminate B

If Charles had spent half as much time attending his classes as he did complaining about them, he would have been a good student.

A. had spent half as much time attending his classes as he did complaining
B. had spent half as much time to attend his classes as he did to complain
C. were to spend as much time attending his classes as he does complaining
D. were to spend half as much time attending his classes as complaining
E. should spend half as much time attending his classes as to complain

Here, the key is to notice "If...THEN" clause which is a conditional.
This is valid even if "then" is not used.
After you have noted that, S-V pair must agree.

This only agrees for past perfect + would have
eg: If Sam had played with any toy, it would have been his remote controlled airplane. (would have verb)

With this, you can eliminate all options except A and B.

Of the two, you must eliminate the one which sounds more awkward.

Hence, OA is A

In this question ATTENDING is used as Verb+ing modifier or not? If yes then how it is modifying nearest noun that is TIME???

Hi, can someone answer this?

Had the sentence been..
"If Charles had spent half as much time attending his classes as he did complaining about them, he could have been a good student."

Option D would have been right?

had spent half as much time to attend his classes as he did to complain
to attend and to complain are incorrect.
the sentence needs nouns here and to attend and to complain are acting as verb.
_________________

thanks - why does it need nouns though?

to + ver ing = Infinitive, check the sentence needs a noun, hence we can reject option (B)
_________________

look at verb spend in the dictionary,
spend on doing
spend doing
are idioms.

hoep it helps.

To+verb shows intention or purpose of the subject. In option B use of To+verb indicates that Charles had an intention of doing what he did. This is not what the sentence intends to mean. Instead action of Charles has happened already. Option B can be eliminated.
Options C, D & E can be eliminated for incorrect use of If...then tense forms.
Option A is the best choice.

GMATNinja
Why subjunctive mood is not applicable here?

Posted from my mobile device

1. Why is B incorrect? IMO, not because it is awkward but because there is no intention or purpose implied in Charles’ behavior. It is more of a random happening. Therefore, the infinitive distorts the meaning
_________________

daagh, no sir, I meant why option C and D are incorrect? As they set indicate subjunctive mood, I thought they made more sense than others.Am I missing something here? Thanks sir.

Posted from my mobile device

Adi
If Charles had spent half as much time attending his classes as he did complaining about them, he would have been a good student.

A. had spent half as much time attending his classes as he did complaining
B. had spent half as much time to attend his classes as he did to complain
C. were to spend as much time attending his classes as he does complaining
D. were to spend half as much time attending his classes as complaining
E. should spend half as much time attending his classes as to complain


C. were to spend as much time attending his classes as he does complaining
D. were to spend half as much time attending his classes as complaining

As far as I see, all the first four choices are essentially past subjunctive mood clauses. If you are asking why both the above choices are incorrect despite being subjunctive, then the answer lies in that, both of them flout the conditional norms.

Choices C and D are past subjunctive mood sentences as they talk about some unreal or impossible happenings that can not happen now, as the non-underlined part (would have been) points to a bygone event. However, the use of ‘would have been’ entails that the subordinate clause has to use a past perfect verb as - had spent - and not a simple past such as “were”. C is particularly more wrong as it says ‘as much time’ and not ‘half as much time’.


_________________

daagh sir, I got your point. Thanks a lot.

Posted from my mobile device

Without noun also sentence is making sense. Didn't get you.

Why option B is incorrect ?