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OG 10 Sentence Correction Query

Expert replies
by kushagra09 » Sun Aug 14, 2011 7:00 am
211. The period when the great painted caves at
Lascaux and Altamira were occupied by Upper
Paleolithic people has been established by carbon-
14 dating, but what is much more difficult to
determine are the reason for their decoration, the
use to which primitive people put the caves, and
the meaning of the magnificently depicted
animals.
A) has been established by carbon-14 dating, but
what is much more difficult to determine are
B )has been established by carbon-14 dating, but
what is much more difficult to determine is
C )have been established by carbon-14 dating,
but what is much more difficult to determine
is
D )have been established by carbon-14 dating,
but what is much more difficult to determine
are
E) are established by carbon-14 dating, but that
which is much more difficult to determine is
Two instances of subject-verb agreement must be
observed in this sentence: The period ... has been
established and what is much more difficult to
determine ... is. Both clauses have singular subjects and
must have singular verbs. Only B, the best choice,
observes these requirements. A incorrectly uses the plural
form are in the second clause. Choices C and D incorrectly
use the plural form have in the first clause, and D
incorrectly uses are in the second clause as well. E
incorrectly uses the plural form are in the first clause.
Furthermore, because the date of the period in question
was established before the writing of the sentence, the
verb of that clause must be in the present perfect form
(has been established).

I have a problem with the explanation, in the second part of the underlined sentence which uses is should be are because here we are talking about three different things which also closes with and and hence the answer should be A.


Kindly help friends.
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Source: — Sentence Correction |

by krishnasty » Sun Aug 14, 2011 8:12 am
I assume that the OA is 'B'.

As pointed out in the explanation, look at the word which is connected to is/are...it says that the reason.....is....and not reasons are.. for example,

"the reason for his failure is his lack of commitment"..correct
"the reasons for his failure are his lack of commitment and something something"..

if you notice, we are kind of stuck with the word 'reason' coz thats something we cant change. hence, option B is correct..
---------------------------------------
Appreciation in thanks please!!
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by adi_800 » Sun Aug 14, 2011 11:40 am
krishnasty wrote:I assume that the OA is 'B'.

As pointed out in the explanation, look at the word which is connected to is/are...it says that the reason.....is....and not reasons are.. for example,

"the reason for his failure is his lack of commitment"..correct
"the reasons for his failure are his lack of commitment and something something"..

if you notice, we are kind of stuck with the word 'reason' coz thats something we cant change. hence, option B is correct..
I don't think you are eliminating A for correct reasons..
Rule: Subjective phrases are always singular and hence take singular verb..
Subject phrase: What is much more difficult to determine and hence is should be used..
What is difficult to determine...

1. the reason for their decoration,
2. the use to which primitive people put the caves,
and
3. the meaning of the magnificently depicted
animals.
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