Since 1990 the global economy has grown more than it did

[chenche8827]

still waiting for response.> <

[jnelson0612]

sorry to dig these old problem again.
My question is :

about D,E : exceeds what it has been
exceeds what it did


what means "the thing that" is that correct?
if so,then "it" here is useless ， since the sentence can be rewrited like "exceeds the thing that it has been" . Therefore we can eliminate D E because of the usage of "what"?

chenche, here is Ron's explanation of why D and E are wrong:

"Yeah, you can't use the present perfect if the time interval is over. If the trend continues into the present day, then the present perfect is appropriate.

Even if that were fixed, choice D still suffers from fatal wordiness / lack of concision, especially in comparison to the correct choice."

"E) The growth of the global economy since 1990 exceeds what it did for the 10,000 years from the beginning of agriculture.

'what it did' doesn't make any sense:
* the growth didn't 'do' anything
* there's no other verb to which 'did' could logically be parallel to complete the comparison"

[saptadeepc]

Too late to bump in this thread, but not too late to learn more :-)

Can we eliminate by using the difference in meaning between "it" and "that" ?

"that" does not mean the same thing, it means a similar COPY or another instance of what we are talking about.

In option 'B', "that" means another copy of the global economy, which is not correct.
The same instance of global economy has grown more.

Therefore, "it" has grown more.

Hence can we directly eliminate B,C . D,E are incorrect coz of reason cited by Ron.

[abidshariff009]

I know its been running for two years now, but I have a problem here with the OA. I still don't understand how "did" fit in here". Instead it has to be "had"..

I mean the correct ans has to be "Since 1990 the global economy has grown more than it had during the 10000 years from the beginning of agriculture

Because "during one time to another is a continuous process that started somewhere in the past and ended in1950. So past perfect fits in here. From where and why "did" pop up?

[RonPurewal]

I know its been running for two years now, but I have a problem here with the OA. I still don't understand how "did" fit in here". Instead it has to be "had"..

I mean the correct ans has to be "Since 1990 the global economy has grown more than it had during the 10000 years from the beginning of agriculture

Because "during one time to another is a continuous process that started somewhere in the past and ended in1950. So past perfect fits in here. From where and why "did" pop up?

first --
OFFICIALLY CORRECT ANSWERS ARE CORRECT!
do not question officially correct answers!
far too many students on this forum make the mistake of questioning the correct answers; please note that doing so is a complete waste of your time and effort. i.e., exactly 0% of the time that you spend posting "isn't this official answer wrong?" is productive, and exactly 100% of that time is wasted.

"is this correct?" is NEVER a productive question to ask about one of GMAC's correct answers -- the answer is always yes.
"is this wrong?" / "is this X type of error?" is NEVER a productive question to ask about one of GMAC's correct answers -- the answer is always no.

instead, the questions you should be asking about correct official answers, if you don't understand them, are:
"why is this correct?"
"how does this work?"
"what understanding am i lacking that i need to understand this choice?"

this is a small, but hugely significant, change to your way of thinking -- you will suddenly find it much easier to understand the format, style, and conventions of the official problems if you dispose of the idea that they might be wrong.

--

when a specific timeframe is given, the simple past is almost always the correct tense.

[ntr1989512]

hi ron!
Why A is correct?
i very suspect the usage of "it" in choice A! since in the comparison structure, we often use "that" or "those" to refer to the related thing in the first half of the sentence!
pls, what "it" refers to ?? can i substitute "it" for "that"??
thanks in advance

[tim]

no, you have to use "it" here, and "it" clearly refers to the global economy..

[ntr1989512]

no, you have to use "it" here, and "it" clearly refers to the global economy..

sorry, i still confused about "it"
why? can't "that" refer to "global economy"?
i see many many comparison constructions that use "that"or"those" to refer to specific noun in early sentence!
any difference between "that" and "it"??

[tim]

because the correct answer is A. your task should not be to ask what other possibilities would work for a correct answer, but to understand why the correct answer is acceptable and what's wrong with the others. in other words, you should focus not on whether "that" would work but on understanding that "it" is acceptable..

[vikram4689]

I've learned one rule on the basis of which I marked off A, but now I'm very confused.

Rule: when "have/has/had" is an aulixiary verb, you do have a choice to repeat or not repeat the past participle, but you cannot change "have/has/had" to "do/does/did"

For example:
John has always eaten more meat than Paul has eaten.(correct)
John has always eaten more meat than Paul has. (correct)
John has always eaten more meat than Paul does. (incorrect)

A says: Since 1990 the global economy has grown more than it did during the 10,000 years from the beginning of agriculture to 1950

If OA is A, then it is voilating this rule.

The only difference I can point out between the rule and the choice A is that the above mentioned rule has 2 different subjects while choice A has only one subject.

Could any instructor clarify on the same?

read here:
http://www.beatthegmat.com/soar-t62473-15.html#280069

note that this sentence fits the third form given in that post -- "did" is a form of "to do", and "has grown" is a tense of the action verb "grow" (it's called the "present perfect tense", if you like to name these things)

notice that the reverse of this kind of structure would not be permissible; if you had just "has" as the second part of the parallel structure, then that's no longer the present perfect tense of an action verb, and so in that case you would also need a corresponding form of "have" in the first part.

can you please explain why blue part above is correct whereas "Joe WAS EATING as fast as Maggie DID" is incorrect. To me both seem to comply to rule 3 in given link

[tim]

i don't see how the blue part is relevant to your question, but the problem here is that you are comparing two tenses that cannot be compared because one indicates an ongoing process and the other indicates a specific point in time. this is definitely not within the purview of rule 3 that you reference in Ron's other post..

[youlimeng325]

Hi, masters:
I understand the reason why A is correct and I do not intent to question the correct answer.
However, I am a little confused about the comparsion elements in this question.
Can I just compare the two different periods and do not mention "it did"?
Is this statement correct?
Between 1990 and 2000 the global economy grew more than during the 10,000years from the beginning of agriculture to 1950.
Thank you very much!

[jlucero]

Hi, masters:
I understand the reason why A is correct and I do not intent to question the correct answer.
However, I am a little confused about the comparsion elements in this question.
Can I just compare the two different periods and do not mention "it did"?
Is this statement correct?
Between 1990 and 2000 the global economy grew more than during the 10,000years from the beginning of agriculture to 1950.
Thank you very much!

In this sentence, no. There's always other ways of properly getting a meaning across, but you have to understand that this construction is trying to compare how "the economy grew (clause)" to something else. The something else needs to be a clause which must include a verb.

Many of the incorrect answer choices try to change the meaning here to compare the economy's growth (noun), but they don't have the proper comparison. The sentence could be correct if it properly compared:

The growth during X exceeded that during Y.

But none of the other answer choices do this correctly. The takeaway is to spot when things are being compared versus when the actions of a thing are being compared.

[aditya8062]

Since 1990 the global economy has grown more than it did during the 10,000 years from the beginning of agriculture to 1950.

A) Since 1990 the global economy has grown more than it did during the 10,000 years from the beginning of agriculture to 1950.
B) Since 1990 the growth of the global economy has been more than that during 10,000 years, from when agriculture began.
C) The growth of the global economy since 1990 exceeds that which had been for 10,000 years from the beginning of agriculture.
D) The growth of the global economy since 1990 exceeds what it has been for 10,000 years, from when agriculture began
E) The growth of the global economy since 1990 exceeds what it did for the 10,000 years from the beginning of agriculture.

i have posted the question again as this thread is too long
the OA is A
though i dont intend to question the OA BUT I HAVE THE FOLLOWING DOUBT :
in one of the post of ron i read the following :
whenever you use a parallel structure with omitted/elided words, the EXACT omitted word(s) MUST be present, IN PARALLEL STRUCTURE, elsewhere in the sentence. this means in exactly the same form - no alterations, no tense changes, no nothing

ron had written this reply while answering as why option C IN THE following question (red colour ) is wrong
Soaring television costs accounted for more than half the spending in the presidential campaign of 1992, a greater proportion than it was in any previous election.

A. a greater proportion than it was
B. a greater proportion than
C. a greater proportion than they have been
D. which is greater than was so
E. which is greater than it has been

he said the following abt option c
this kills choice (c). that choice contains "...than they have been...", which omits a participle: in other words, it's actually "...than they have been ______", where the ______ is clearly seen to be accounting (for).
since the EXACT WORD accounting doesn't appear anywhere else in this sentence, the sentence is incorrect.

now if i look the option A (blue color question ) then i find that "did " does no go with "grown " .
"did " can go with "grow " but that verb tense in not there in the first part of the sentence .
also i quoting one sentence from your manahttan sc book 4 th edition page 249 with the following rule :
the first instance of the verb should usually match the helping verb in the tense .if u need to change tense ,repeat the whole verb in the new tense
wrong : i have never seen as aardvark,but last year my father did .
right :i have never seen as aardvark,but last year my father saw one
can ron plz explain as why this rule is not voilated in the correct option (A ) of the blue queation

thanks and regards

[RonPurewal]

also i quoting one sentence from your manahttan sc book 4 th edition page 249 with the following rule :
the first instance of the verb should usually match the helping verb in the tense .if u need to change tense ,repeat the whole verb in the new tense
wrong : i have never seen as aardvark,but last year my father did .
right :i have never seen as aardvark,but last year my father saw one
can ron plz explain as why this rule is not voilated in the correct option (A ) of the blue queation

thanks and regards

that's not accurate. in fact, one of the prime uses of helping verbs in parallel constructions is to express the same verb in a different tense.

we may already have gotten rid of that "rule" in the 5th edition books. do you have those? if so, is it still there? (i am traveling and don't have the books with me.)
if it's still there, please let us know, so that we can mark it for removal in the next edition. thanks.