SC -- Confusing modifiers

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SC -- Confusing modifiers

by Stockmoose16 » Thu Aug 07, 2008 12:03 pm
Based on the growth rates of large modern reptiles such as the Galapagos tortoise and examinations of fossils of juvenile dinosaurs, scientists estimate that the largest dinosaurs probably lived to be between 100 and 200 years old.
(A) Based on the growth rates of large modern reptiles such as
(B) On the basis of growth rates of large modern reptiles such as
(C) Based on the growth rates of large modern reptiles like
(D) On the basis of growth rates of large modern reptiles, like those of
(E) Based on such growth rates as those of large modern reptiles like




THE OA is B. The going explanation is that "Scientists" can't be modified by 'based on'." I don't understand. The sentence reads, "Based on the growth rates... scientists estimate that the largest dinosaurs." To me, that sentence doesn't sound like "scientists are based on growth rates." It says, "scientists make estimates BECAUSE OF growth rates." What am I missing here? Can someone explain in layman's terms?
Source: — Sentence Correction |

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by vish150783 » Thu Aug 07, 2008 6:09 pm
I think the error is in the usage of Based upon. It can be based on an idea or story, but it cannot be based on the data. It has to be on the basis of the data.

Others can correct me if I am wrong.

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by iwill » Thu Aug 07, 2008 10:35 pm
IMO B.

Like cannot be used to give examples. SO C,D,E can be ruled out.
I m not sure abot Based on/ On the basis of..
please explain.

Thanks
Iwill

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Based on Vs On the basis of

by sharekhs » Thu Aug 21, 2008 10:04 pm
Hi

I have also encountered a similar question in OG 11 / Verbal Review, where you have to choose between 'on the basis' / 'based on' , and the solution says that only when considering one of them , you need to know, what is it affecting? i mean to say in this question, 'based on X scientist', is not preffered over 'on the basis of X scientists', if you read this without the phare in between (X), I think B should be the answer.

Regards

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by mksreeram » Fri Aug 22, 2008 1:45 am
A) Based on X and Y, scientists estimate

B) on the basis of X and Y, scientists estimate

1st sentence says scientists are based on
2nd sentence says scientists on the basis of x and y estimate

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by dileepsinha » Fri Aug 22, 2008 4:02 am
Based on the growth rates (of large modern reptiles (such as the Galapagos tortoise) and examinations of fossils (of juvenile dinosaurs), the estimation was made(scientists estimate) that the largest dinosaurs probably lived to be between 100 and 200 years old.

Does it help to clarify?

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by Vignesh.4384 » Fri Aug 22, 2008 5:31 am
Bet ween A and B it is B .

There is a tense problem in A.
Based -> past tense while the other part of the sentence is in present tense ..
B corrects the error above

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by James_83 » Fri Aug 22, 2008 10:47 pm
@@Vignesh

I dont find any tense problem in Choice A.

A simply says

Based on
a)the growth rates of...
b) the examinations....

so,both are parallel.

Actual problem is of modifier.

"Based on ...", actually modifies scientists.

eg :- Based on my score in gmat, i will apply in universities. ---A
On the basis of my score in gmat, i will apply in uni. ----B

So,in layman's language, sentence A is actually modify I. "I" is not based on the score.
Sentence B simply ask the question "who" and the immediate sentence clearly answers this.

So,this similiar pattern is followed here.

Hope this would be fine. Please correct me if i am wrong.

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by wonder » Fri Aug 22, 2008 10:56 pm
@James_83, you are right. good example!

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by Vignesh.4384 » Sat Aug 23, 2008 1:10 am
James_83 wrote:@@Vignesh

I dont find any tense problem in Choice A.

A simply says

Based on
a)the growth rates of...
b) the examinations....

so,both are parallel.

Actual problem is of modifier.

"Based on ...", actually modifies scientists.

eg :- Based on my score in gmat, i will apply in universities. ---A
On the basis of my score in gmat, i will apply in uni. ----B

So,in layman's language, sentence A is actually modify I. "I" is not based on the score.
Sentence B simply ask the question "who" and the immediate sentence clearly answers this.

So,this similiar pattern is followed here.

Hope this would be fine. Please correct me if i am wrong.
good that u hav pointed this out

Ideally this sentence should be

On the basis of growth rates of large modern reptiles such as the Galapagos tortoise and on examinations of fossils of juvenile dinosaurs, scientists estimate that the largest dinosaurs probably lived to be between 100 and 200 years old.

On the basis of growth rates of large modern reptiles such as the Galapagos tortoise --> clause1

on examinations of fossils of juvenile dinosaurs --> clause

Those 2 clause should hav been joined by a conjunction and.

Option A would be correct i guess.. If u add on in the second part of the clause.


The preposition on does not have to be repeated .. so the second time it is removed.

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by dileepsinha » Sat Aug 23, 2008 7:34 am
Vignesh
Even if you add an "on" in the second clause (On is understood in the second clause though), A would still be incorrect, as it would be modifying scientists........

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by stubbornp » Sat Aug 23, 2008 9:24 am
hey guys,First i also chose B....

but...just take a look at D...

why it is wrong???

correct grammer

growth rates of reptiles like those of ......

Is D is out due to change in original meaning...

plz advice...

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