PREP-SC-02

2.        

Organized in 1966 by the Fish and Wildlife Service, the Breeding Bird Survey uses annual roadside counts along established routes for monitoring of population changes of as many as, or of more than 250 bird species, including 180 songbirds.

(A) for monitoring of population changes of as many as, or of

=> we need to use to.

(B) to monitor population changes of as many, or

=> as many (as) is correct.

(C) to monitor changes in the populations of

(D) that monitors population changes of

=> It seems that the routes monitors.

(E) that monitors changes in populations of as many as, or

=> It seems that the routes monitor.

Explanation:

Why does the survey use roadside counts?

=> To do something.

We need “to + verb”

Answer is C.

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To meet the rapidly rising market demand for fish and seafood, suppliers are growing fish twice as fast as their natural growth rate, cutting their feed allotment by nearly half and raising them on special diets.

(A) their natural growth rate, cutting their feed allotment

(B) their natural growth rate, their feed allotment cut

(C) growing them naturally, cutting their feed allotment

(D) they grow naturally, cutting their feed allotment

(E) they grow naturally, with their feed allotment cut 

 Explanation:

Explanation:

1. “As fast as” needs a clause after it.

=> This eliminates A, B, and C.

2. “Comma + Verbing” modifies the preceding clause. In every clause there must be a subject and a verb.

=> A and C do not have clause before “comma + verbing”.

3. “Cutting X and raising Y” is the parallelism.

Option E fails to maintain parallelism.

Answer is D.

Two sc tips.

Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science. E.    they believe to be of "Believe x to be y." => In the context of this sentence, the infini­tive to be is more appropriate than the limited present-tense is in referring to an event that occurred long ago but has been discovered only recently.

People tend to overestimate the amount of energy used by equipment, such as lights, that are visible and must be turned on and off and underestimate it when used by other equipment. -> Karim will overestimate the number when used by a grade. => This sentence is wrong because it nonsensically menas that Karim is used by grade.   when used by: à Nonsensically suggests that  the people are used by equipment.       When used by/if used by retains the subject of the verb.

GMAT sentence correction: Which materials should be studied.

The following materials are from official source:

1. Official Guide 10th edition.
2. Official Guide 11th edition.
3. Official Guide 12th edition.
4. Official Guide Verbal Review.
5. GMATPREP questions.

I am going to post all the concepts one after another in different posts.