Forecast

[vikram4689]

sorry if i hurt you. i was trying to learn the correct structure and had no such intention. nevermind, as suggested, i stop this discussion.

thanks

[tim]

LOL you didn't "hurt" me, but you're probably hurting yourself if you focus on irrelevant issues. it's admirable that you want to understand everything about a sentence, but ultimately if you're trying to improve your GMAT score you should move more of your attention over to issues that the GMAT considers important..

[vijay19839]

In the below Ron's Post, Can someone please explain how 'do' can be replaced by 'know' which is part of To-Infinitive? I thought 'do' replaces the verb but here it is replacing the To-Infinitive verb. Can 'do' replace even Base verbs of the To-Infinitives?


Thanks
Vijay

Hi Ron,

In one of the other threads that I have seen (and I am sure that in several others), you mentioned that in parallel constructions, if the verb in the second part of the construction is "absolutely the same" as in the first part of the construction, then that verb may be omitted in the secod part.

My question is: Can't the above principle be applied to Choice A above since the omitted portion in the second part, i.e. "they know" has the exaclty same verb as the first part?

Thank you for your help.

yep, i did say that. unfortunately, that principle does not apply here, since the verb that you're trying to omit is not exactly the same as its counterpart.
specifically, the first verb is in a hypothetical/conditional tense (would have to know...), while the second verb is in the present tense (they do [= know] now). you are not allowed to imply such tense transitions.
if you omit the verb, the omitted verb will be assumed to be in the same tense as its parallel counterpart. since you have to change tenses in this problem, you must include both verbs.

[RonPurewal]

Can 'do' replace even Base verbs of the To-Infinitives?

the short answer:
yes.

[ikuta.yamahashi]

yep, i did say that. unfortunately, that principle does not apply here, since the verb that you're trying to omit is not exactly the same as its counterpart.specifically, the first verb is in a hypothetical/conditional tense (would have to know...), while the second verb is in the present tense (they do [= know] now). you are not allowed to imply such tense transitions.
if you omit the verb, the omitted verb will be assumed to be in the same tense as its parallel counterpart. since you have to change tenses in this problem, you must include both verbs.

Dear Ron:
I have a question about the s-v omission.
Could you help to confirm the examples below?
1. parking spots are disappearing much more quickly today than they were yesterday.
2. parking spots are disappearing much more quickly today than yesterday.
3. I walk as fast now as I walked when I was younger.
4. I walk as fast now as when I was younger.

IMO all the the example is acceptable, but both they were and I did are not presented in the same tense at the parallel counterpart. So, that is what i am confusing here, why those different tense s-v pairs can be omitted? (BTW the 3rd & 4th examples are from MGMAT sc gudie)

Please help~

[jlucero]

Dear Ron:
I have a question about the s-v omission.
Could you help to confirm the examples below?
1. parking spots are disappearing much more quickly today than they were yesterday.
2. parking spots are disappearing much more quickly today than yesterday.
3. I walk as fast now as I walked when I was younger.
4. I walk as fast now as when I was younger.

IMO all the the example is acceptable, but both they were and I did are not presented in the same tense at the parallel counterpart. So, that is what i am confusing here, why those different tense s-v pairs can be omitted? (BTW the 3rd & 4th examples are from MGMAT sc gudie)

Please help~

I agree with your four examples all making sense, because there's only one logical way to understand those sentences. If you tried to put in the illogical verb (I walk as fast now as I walk when I was younger), the sentence doesn't work. The key thing about 2&4 is that there is a very specific time frame (and in 4's case, another past tense verb "was") that the action MUST take place in. But if you switched around the order of events, you might lead to ambiguity:

Yesterday, I walked around more slowly than today.

Does that mean:
Yesterday, I walked around more slowly than I walk today?
Yesterday, I walked around more slowly than I walked today?

This is where repeating a verb is necessary for clarity. Same for helper verbs:

I could have run faster yesterday than today.

Does that mean:
I could have run faster yesterday than I could have today?
I could have run faster yesterday than I did today?

[vietmoi937]

Hi Ron,

as far as i know, "would" is always used in a construct where we are dealing with "past tense".
When i was working out this problem, i just eliminated the options "would"
Can u plz shed some light on this..

"WOULD" AND "COULD"
These words have 2 different incarnations.

Usage #1
"Would" is the past tense of "will", and "could" is the past tense of "can".
e.g.
According to his most recent advertisement, Mookie the Bookie can predict with 100% accuracy which teams will win next week’s games.
vis-à-vis
His October 2, 1982, advertisement declared that Mookie the Bookie could predict with 100% accuracy which teams would win the following week’s games.

Usage #2
"Would" and "could" are used to describe hypothetical situations that are not true, or are extremely unlikely. (since these situations are hypothetical -- i.e., they never happened -- they don't really have a timeframe.)
e.g.
If I had one million dollars, I could buy 800,000 hamburgers at the gas station.
If I had one million dollars, I would donate 800,000 hamburgers to the county food bank.

--

in this problem "would" is the second type.

great Ron,

grammar books said that "would" can be use in present time to imply a LESS DEFINITE action or more polite way than "will"

so, there is case 3 for "would".

I think D fall into case 3, not case 2, because there is no evidence that the action in D is nearly impossible to happen. We do not have impossible action in D.

[tim]

I don't think I have ever seen that third option used in a correct GMAT sentence. Remember, "grammar books" (can you provide a source BTW?) will often steer you in the wrong direction because the GMAT has its own conventions that do not always agree with other sources. Your best bet is to stick to reputable sources of information about the GMAT specifically.

[ashish-mohan]

in A and E you are not comparing similar things

demographers have to know a great deal more than now about social and economic ...

literally you're comparing the knowledge about social and economic determinants to now.

Hi Ron, you have mentioned that this poster is "correct". What is slightly confusing me is that this poster has "highlighted" "a great deal" and "now" and then says that "knowledge" is being compared with "now.

[RonPurewal]

Do you understand why the comparison isn't parallel? If so, that's the only thing that matters.

[chetan86]

Hi,

If the answer choice would have been
D. would have to know a great deal more than they have now about the social and economic

Instead of
D. would have to know a great deal more than they do now about the social and economic

then the option D could have been right??

Because I thought 'Do' can be used when any action is taking place.
E.g. Tom was working faster than he do now.

But if we have statement like below:
I had more money than I have now. --> Can we use here 'Do' instead of 'Have'?

I think in above sentence 'I do have now' will work fine but omitting 'Do' is fine?

Please let me know your opinion on usage of 'Do'.

Thanks,
Chetan

[RonPurewal]

You can only use "have" if one of the following is true:

1/
It's actually parallel to another form of "to have" (= to possess).
I had more money last year than I have now.
(identical to I spent more money last year than I spend now.)
Here, "have" is NOT a helping verb; i.e., it's not "have ___ed".

2/
It's a helping verb. It implies "have ___ed", parallel to some verb on the other side.
I am now making more money than I ever have before.
(= "have made")

In your hypothetical version of choice D, neither of these is true.
Not #1, because the other side is not "have knowledge" (= possess knowledge).
Not #2, either. If you interpret "have" as a helping verb, then it implies have known, which is nonsense in the timeframe of "now".

Most importantly, don't edit GMAC's sentences.
If you want to ask questions like this one, it's best to create your own"”SIMPLER"”sentences.

[soulwangh]

You can only use "have" if one of the following is true:

1/
It's actually parallel to another form of "to have" (= to possess).
I had more money last year than I have now.
(identical to I spent more money last year than I spend now.)
Here, "have" is NOT a helping verb; i.e., it's not "have ___ed".

2/
It's a helping verb. It implies "have ___ed", parallel to some verb on the other side.
I am now making more money than I ever have before.
(= "have made")

In your hypothetical version of choice D, neither of these is true.
Not #1, because the other side is not "have knowledge" (= possess knowledge).
Not #2, either. If you interpret "have" as a helping verb, then it implies have known, which is nonsense in the timeframe of "now".

Most importantly, don't edit GMAC's sentences.
If you want to ask questions like this one, it's best to create your own"”SIMPLER"”sentences.

Hi Ron,

I am now making more money than I ever have before.

In Mgmat SC, Chapter 13: Helping Verb, the author says the following sentence is wrong :
I have never seen an aardvark, but my father did.
Because the first instance of the verb does not match the helping verb in tense.

Comparing your sentence to this one, I am confused.
It seems the Mgmat sentence is correct in your opinion.
Am i right?

Could you please give some general rules about help verb?
EG: If the first clause has "have done", can I use "do" or "did" to express a new tense but short version of the verb “done”？

Thanks very much.

[RonPurewal]

The aardvark sentence is ok, if some sort of timeframe is appended to "did" (e.g., but my father saw one yesterday). It will be edited in the next edition of the book.

[GeorgiaF924]

Dear Ron or Tim,

I'm confused why "I have higher bills than last year" is right(From Manhattan 6th edition page 101 ) and "They have to know more than now“ is wrong (from OG 42)

Please help judge if the following sentences or understandings are correct.
sentence 1: They have to know more than they do now.
sentence 2: They have to know more than they know now.
sentence 3: They have to know more than now.
sentence 4: They will know more than now.

my judgement is : right,right,wrong,right. Am I right?
my poor understanding is: Although the tense is different (future and current ), if one compares to itself (of different period), and the verb has appeared in the former part of the sentence, then the verb can be omitted. But in sentence 3, "have to know" is different from "know"(i.e, they are different verb phrases), so the latter"they do" can't be omitted.

Am I right? Can you kindly help me figure out these problems? very dizzy now.....