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Supernova

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by GmatKiss » Thu Feb 16, 2012 5:37 am
Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

OA after some discussion
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by Anshu Nadir » Thu Feb 16, 2012 6:20 am
Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is [unneccessary]
(B) that they believe it to be
(C) they believe that it is of awkward construction
(D) they believe that is
(E) they believe to be of awkward construction


Correct answer should be D.
Please feel free to add/correct any of the explanations provided above.

Regards,
Anshu Nadir
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by neerajkumar1_1 » Thu Feb 16, 2012 6:34 am
The trick here is that one should probably not jump to the last answer because of the favorable idiom: believe to be.

IMO: A
A: verb is consistent with the rest of the sentence and believe is correctly used.
B: it is redundant.
C: same as b and awkward. 'of a type' is unidiomatic
D: unidiomatic
E: again 'of a type' unidiomatic

Also, the correct idiom is 'believe x to be y'
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by sam2304 » Thu Feb 16, 2012 9:57 am
Believe to be is the idiom here.

A/B - that is not necessary
C - it is of - wrong
D - that is - wrong

IMO E.
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by GMATGuruNY » Thu Feb 16, 2012 4:43 pm
GmatKiss wrote:Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

OA after some discussion
A, B and D each imply that ONE -- all on its own -- is a TYPE. ONE example cannot by itself constitute a TYPE. Eliminate A, B and D.

In C, one and it are redundant, each referring to the explosion. Eliminate C.

The correct answer is E.
Last edited by GMATGuruNY on Fri Feb 17, 2012 5:35 am, edited 2 times in total.
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by neerajkumar1_1 » Thu Feb 16, 2012 7:53 pm
GMATGuruNY wrote:
GmatKiss wrote:Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

OA after some discussion
A, B and D each imply -- incorrectly -- that the explosion is a type. The EXPLOSION itself is not a type; it is one OF a type. Eliminate A, B and D.

In C, one and it are redundant, each referring to the explosion. Eliminate C.

The correct answer is E.
hey mitch..
I suppose i overdid the problem... but still need to clarify..
Don't we usually say 'x is a type of something' rather than 'x is of a type of something'
also for the idiom believe to be...
isnt the correct way of using it is ' believe x to be y'

thanks..
nk
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by GMATGuruNY » Thu Feb 16, 2012 8:19 pm
neerajkumar1_1 wrote:
GMATGuruNY wrote:
GmatKiss wrote:Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

OA after some discussion
A, B and D each imply -- incorrectly -- that the explosion is a type. The EXPLOSION itself is not a type; it is one OF a type. Eliminate A, B and D.

In C, one and it are redundant, each referring to the explosion. Eliminate C.

The correct answer is E.
hey mitch..
I suppose i overdid the problem... but still need to clarify..
Don't we usually say 'x is a type of something' rather than 'x is of a type of something'
also for the idiom believe to be...
isnt the correct way of using it is ' believe x to be y'

thanks..
nk
All on its own, ONE does not constitute a TYPE.
What we SAY and what is CORRECT are not always the same.
Someone might walk by a skyscraper and SAY the following: This building is a type I like.
The wording here sounds natural but is technically incorrect: the ONE building does not constitute a TYPE of building.
The following would more properly convey the intended meaning: This building is an EXAMPLE of a type I like.

Yes, believe X to be Y is correct, as is X is believed to be Y.
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by GmatKiss » Tue Feb 21, 2012 4:50 am
Thanks all, OA is E
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by aflaam » Mon Jan 18, 2016 3:21 am
Hello Mitch,
Can B and C be crossed also because one is reffering to supernova and pronoun it also refers to supernova. two pronouns" it" and "one" have the same referent.
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by GMATGuruNY » Tue Jan 19, 2016 7:38 am
aflaam wrote:Hello Mitch,
Can B and C be crossed also because one is reffering to supernova and pronoun it also refers to supernova. two pronouns" it" and "one" have the same referent.
Thanks
This line of reasoning -- that two different pronouns cannot not have the same referent -- is valid.
However, the referent for one and it is not supernova but explosion.
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by aflaam » Tue Jan 19, 2016 8:45 pm
Mitch please confirm,
A) that they believe is
one refers to explosion and that also refers to explosion, therefore wrong

But in B,
B)that they believe it to be
one, that, it all refer to explosion
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by vishalwin » Tue Jan 19, 2016 10:36 pm
GMATGuruNY wrote:
GmatKiss wrote:Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.

(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

OA after some discussion
A, B and D each imply that ONE -- all on its own -- is a TYPE. ONE example cannot by itself constitute a TYPE. Eliminate A, B and D.

In C, one and it are redundant, each referring to the explosion. Eliminate C.

The correct answer is E.


Hi Mitch,

Can you please help in below doubts:

1) In C, one and it are redundant, each referring to the explosion. --> How are they redundant?

2) In both options B & C "THAT" & "IT" refers to Explosion? am I right?
Thanks & Regards
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by GMATGuruNY » Wed Jan 20, 2016 4:07 am
aflaam wrote:Mitch please confirm,
A) that they believe is
one refers to explosion and that also refers to explosion, therefore wrong
A: a supernova explosion, one that they believe
Technically, one serves to refer to explosion, while that serves to refer to one.
But in B,
B)that they believe it to be[
one, that, it all refer to explosion
B: a supernova explosion, one that they believe it
Here, one serves to refer to explosion, while that serves to refer to one.
It is not crystal clear whether it serves to refer to one or to explosion.
Regardless, all three pronouns -- at least semantically -- refer to the same antecedent: a supernova explosion.
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by GMATGuruNY » Wed Jan 20, 2016 4:22 am
vishalwin wrote:1) In C, one and it are redundant, each referring to the explosion. --> How are they redundant?
C: one they believe that it is of a type
Since both one and it seem to refer to supernova explosion, we get:
a supernova explosion they believe that the supernova explosion is of a type.
The repetition of supernova explosion is both redundant and nonsensical.
2) In both options B & C "THAT" & "IT" refers to Explosion? am I right?
As noted above, C conveys the following meaning:
a supernova explosion they believe that the supernova explosion is of a type.
Here, that does not serve to refer to an explosion.
Rather, the entire that-clause in red serves as the DIRECT OBJECT of believe.
WHAT do astronomers believe?
They believe THAT THE SUPERNOVA EXPLOSION IS OF A TYPE.

In my post directly above, I explain the structure in B.
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by Mo2men » Wed Sep 13, 2017 5:05 pm
GMATGuruNY wrote:
vishalwin wrote:1) In C, one and it are redundant, each referring to the explosion. --> How are they redundant?
C: one they believe that it is of a type
Since both one and it seem to refer to supernova explosion, we get:
a supernova explosion they believe that the supernova explosion is of a type.
The repetition of supernova explosion is both redundant and nonsensical.
2) In both options B & C "THAT" & "IT" refers to Explosion? am I right?
As noted above, C conveys the following meaning:
a supernova explosion they believe that the supernova explosion is of a type.
Here, that does not serve to refer to an explosion.
Rather, the entire that-clause in red serves as the DIRECT OBJECT of believe.
WHAT do astronomers believe?
They believe THAT THE SUPERNOVA EXPLOSION IS OF A TYPE.

In my post directly above, I explain the structure in B.
Dear Mitch,

1- GMAC in its model answer says that "The pronoun that in A and B should be deleted, since the pronoun one is sufficient to introduce the modifier and the sentence is more fluid without that." is it always with 'one'? if yes, is there any other words in line with 'one??

2-Is the verb 'believe that' is correct? Have you seen it compared to 'believe...to be...'?

Thanks
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