Halley’s comet

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Halley’s comet

by mad4gmat » Sat May 30, 2009 10:10 am
Hi Guys,

Not clear with the given answer..though it is already discussed in forum.but need some more clarification..

Because Halley’s comet changes orbit slightly during the seventy-six-year interval between passing close to Earth, it may veer onto a collision course with a planet sometime in the distant future.

(A) between passing
(B) of passing
(C) between its passes
(D) of its passes
(E) as it passes

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by subha_sri8 » Sat May 30, 2009 2:44 pm
During the seventy-six year interval is the key in this sentence.
In this sentence between does not make sense as the meaning states the comet passes close to the earth and not between earth and something.

Therefore eliminate A and C.

D. of it passes sounds awkward.
Between E and B , would choose B .

OA please?

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by mbadrew » Sat May 30, 2009 3:01 pm
D is the correct answer. The key is identifying the subject and verb in this confusing sentence. The question also tests logical sentence construction.

Subject = comet

Verb = passes

Pronoun = its

Logically, when you use between, it has to be related to two objects or subjects. Between earth and what? But the comet can simply pass by the earth.

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by mad4gmat » Tue Jun 02, 2009 5:19 am
OA is C
Anymore takers?
mbadrew wrote:D is the correct answer. The key is identifying the subject and verb in this confusing sentence. The question also tests logical sentence construction.

Subject = comet

Verb = passes

Pronoun = its

Logically, when you use between, it has to be related to two objects or subjects. Between earth and what? But the comet can simply pass by the earth.

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by dendude » Tue Jun 02, 2009 6:51 am
mad4gmat wrote:OA is C
Anymore takers?
mbadrew wrote:D is the correct answer. The key is identifying the subject and verb in this confusing sentence. The question also tests logical sentence construction.

Subject = comet

Verb = passes

Pronoun = its

Logically, when you use between, it has to be related to two objects or subjects. Between earth and what? But the comet can simply pass by the earth.
OA definitely cannot be C. I disagree.
Usage of "interval" along with "between" is not only illogical but also redundant. Interval is enough to suggest a passage of time between two events, and there is no necessity to use the word "between"

mbadrew has correctly identified the necessity of the pronoun its in D.
It correctly provides follow-on onto the next half of the sentence.
Because Halley’s comet changes orbit slightly during the seventy-six-year interval of its passes close to Earth, it may veer onto a collision course with a planet sometime in the distant future.

OA should be D. What is the source of this question?

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by Arsene Lupin » Tue Jun 02, 2009 7:38 am
I can understand why its C. The interval is between the passes. Other choices express illogical meanings.

However, it seems a bit weird for the GMAT. What is the source?

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by mad4gmat » Wed Jun 03, 2009 10:57 am
Arsene Lupin wrote:I can understand why its C. The interval is between the passes. Other choices express illogical meanings.

However, it seems a bit weird for the GMAT. What is the source?
I took it from one of the website and explanation given is as below:

The comet's orbit changes when it is AWAY from earth. It passes by earth every seventy-six years.

E) sounds like the comet changes orbit as it passes by the earth. It may also give the impression that the orbit changes as it passes by the earth for seventy-six years.

You need (C) to express the time away from earth


Now can anybody explain?As I didn't understand the explanation[/b]

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by Stacey Koprince » Thu Jun 04, 2009 10:11 am
Received a PM asking me to respond.

Please do not study stuff that you find on random web sites without sourcing or attribution as to the author of the material. If something feels weird or not GMAT-like, don't study it.

It is actually the case that we need 'between' here. The sentence is referencing the 76-year interval between two passes - the comet passes Earth, then 76 years go by, then the comet passes Earth again.

And that also tells us why to choose C rather than A: if you are going to discuss the interval between, then by definition, you are discussing the interval between two passes. So you actually need to indicate that with the language. "passes" is a noun indicating multiple (plural) passes.

Also, in general, if you see the set-up: during the interval <preposition>, use between: during the interval between <X and Y> or during the interval between <something plural indicating a repeating event>.

During the interval between freshman year and senior year, she got straight As.

During the regular interval between classes every day, she always goes to the library to study.
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