Less than 35 years after the release of African honeybees outside Sao Paulo, Brazil, their descendants, popularly known as killer bees, had migrated as far north as southern Texas.

A) Less than 35 years after the release of African honeybees outside Sao Paulo, Brazil,

B) In less than 35 years since releasing African honeybees outside Sao Paulo, Brazil,

C) In less than the 35 years since African honeybees had been released outside Sao Paulo, Brazil,

D) It took less than 35 years from the release of African honeybees outside Sao Paulo, Brazil, when

E) It took less than the 35 years after the time that African honeybees were released outside Sao Paulo, Brazil, and then

Please explain tense structure in A? The past perfect is used to indicate that an action in the past occured before another action in the past. So why is the past perfect used here? ALso what is the best approach to eliminate all wrong answers and arrive at the right one?

please post questions in the appropriate thread - GMATPrep questions have their own threads (math and verbal). Thanks!

_________________
Stacey Koprince
Instructor
Director of Online Community
ManhattanGMAT

this is a tricky one.

if you were narrating in the present tense, you'd say the following: 'as of today, the bees have migrated as far north as southern texas.' therefore, since this sentence describes a situation in the past (it describes the situation 35 years after the release, which is before the present), you translate all present-tense verbs into the past tense. this turns 'have migrated' into 'had migrated'.

there is no explicit description of the 'second event' you're looking for in this problem, which is what makes it difficult. instead, the 'second event' is the point on the timeline, 35 years after the release of the bees. because the sentence describes a trend whose relevance continues up to and through that point, a perfect tense is appropriate.

wrong answers:
* choice b implies that the honeybees' descendants somehow released them (perhaps a very bizarre case of karmic cycles, but absurd no matter what).
* choice c: 'the 35 years since' implies that the present is 35 years after the release date. not only does this conflict with the meaning of the original, but it also renders the past perfect (from the underlined part) inappropriate: you'd need present perfect in this case. also, since the release is a point event, it would belong in the simple past.
* choice d: in this sentence, the commas + non-essential modifier ('..., when') seem to imply that the descendants' migration took place simultaneously with the release of the original honeybees. in addition, in this sentence, 'it' refers to some unspecified event (it can't refer to the descendants' migration, for the aforementioned reasons).
* choice e: all kinds of problems with this one. if you don't see what's wrong with it, reply and we will elaborate.

Just another note - most grammar rules have some rare exceptions, so be aware of that. And some of the rules we follow for the test are not exactly "real world" rules - rather, they blend real-world rules and the reality of the test.

For example, "being" is almost always wrong on the GMAT, but "being" can be used correctly in a sentence. It's just that the GMAT rarely chooses to do so.

By the same token, in the real world, we don't have to have the two events in one sentence because we usually read multiple sentences grouped together, so you can split the past perfect and simple past construction into two different sentences. Thus, it isn't technically a grammar rule that you must have the two in one sentence - it's just that the GMAT gives only one sentence and, therefore, the vast majority of sentences do put both in the same sentence because the sentence needs to indicate somehow that the past perfect is appropriate for the sentence. How else would you decide?

And notice on this one how they don't make you choose yourself - the past perfect part of the construction isn't underlined.

_________________
Stacey Koprince
Instructor
Director of Online Community
ManhattanGMAT

I know that past perfect 'had' generally should be paired with a simple past tense. However, based on what you mention above Stacy, that should not be grounds for canceling an answer choice if the answer choice violates that 'rule'?

i'll try to explain why this is the way that it is. it's a rare form, so, if the following explanation doesn't make sense, you may wish to memorize the problem in this thread instead (or forget all about it, depending on just how wide of a net you want to cast in your studying).

when we use the present perfect, we don't usually have a second event, because the second 'event' is the present. on the other hand, when the time described in a sentence is actually in the past (because of the way the sentence is narrated), then whatever would normally occur in the present perfect must be translated into the past perfect.

here are two examples to illustrate.
it is december 2007; the world record in the discus throw has stood since 1986.
it was july 1991; the world record in the long jump had stood since 1968. --> but it was broken later that year

hope that makes sense.

Ron, your explanation is best among available because I searched this question in various websites.
It's clear as to why we can eliminate BCDE.
However, I find it incomplete in explaning why A is correct.
Let me make my question more concrete :
Why the option A uses "Less than 35 years after..." rather than "In less than 35 years after..." ?

and that is why you should continue to come here. :)



i'm with you on this one; i'd likewise prefer a wording such as 'in less than 35 years after...', because, in my opinion, it better conveys the idea that the migrations took place continuously over the 35-year period. just plain 'less than' seemed to me, and possibly to you as well, to suggest that the migrations might have occurred all at once.

in any case, though, you've got to remember that correctness trumps clarity (and definitely trumps concision as well). therefore, differences in wording, such as this one, are trifling in comparison to actual errors in usage, grammar, diction, or idiom. i think both of us will agree that there is no idiom error in the wording chosen here; it's just a somewhat awkward wording (a situation by no means uncommon on the real test).

Hi Ron/Stacey,
"Less than 35 years...blah blah...", their descendants ...

Doesn't the part in quotes modify their descendants???
I discarded A for the same reason.

Though I agree with you that B,C,D and E have grammatical flaws, A has a major modifier problem!

nope.

'less than 35 years after blah blah' is a TIME modifier, and, as such, must therefore be regarded as an ADVERBIAL modifier.
adverbial modifiers modify the entire action of a clause, not just a single noun. so, this modifier gives the time frame for the entire action described - which is of course exactly what we want to do.

Team,
Please help me on this question, as i am very confused.

What is their descendants in A -
Less than 35 years after the release of African honeybees outside Sao Paulo, Brazil
I guess, "their" is referring to "African honeybees" i.e subject but how can "their" refer to anything following "of" ? I was under the impression that the subject of a clause cannot be in of ....

Please help me !

can some one please answere my question ? Thanks in advance !

can some one please advice.

this has nothing to do with the "subject of a clause"; we're discussing the antecedent of a pronoun, not the subject of a clause.

the pronoun is UNAMBIGUOUS - "african honeybees" is the only possible thing to which "their" can refer - so we're all good here.

by the way, when you do this sort of thing --



all you're doing is knocking your post back to the END of the line.

we answer posts from oldest to newest, so, if you "bump" threads, you are actually consigning your post to the absolute bottom of the inbox.
fyi