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Sentence Correction: Preposition Questions - Split Constructions

Even after looking into and analyzing the evidence, researchers cannot determine if wild birds are carriers of the H5N1 bird flu virus.

This answer choice repeats the original Stylistic error. Although the word whether is a correct replacement for the word if, in the GMAT, the addition of the phrase or not at any point after the word whether is considered redundant. Look for a more concise answer choice.

This answer choice repeats the original Stylistic error. Although the word whether is a correct replacement for the word if, in the GMAT, the addition of the phrase or not at any point after the word whether is considered redundant. Look for a more concise answer choice.

In the GMAT, the word if should be used in Conditionals only. Since in this question there is no condition, if should be replaced by whether.

Think of whether as a choice between two possibilities dealing with the same subject or as a yes/no question.

Example: I do not know whether this will work. (yes or no)

He was not sure whether he wanted banana or chocolate cake. (a choice between 2 possibilities)

Although this answer choice corrects the original Stylistic error by using whether instead of if, it is grammatically incorrect. The verb looking requires a preposition in order to logically connect to the evidence. The researchers looked into the evidence.

What helps us identify this question as a Split Construction question and identify the mistake is the following Stop Sign:

A split construction: Verb A + and/or + Verb B + object

Good work!

In the GMAT, the word
if should be used in Conditionals only. Since in this question there is no condition, this answer choice correctly replaces if with whether.

looking into and analyzing the evidence, researchers cannot determine if wild birds are carriers of the H5N1 bird flu virus
looking into and analyzing the evidence, researchers cannot determine whether wild birds are carriers of the H5N1 bird flu virus or not
analyzing and looking into the evidence, researchers cannot determine whether wild birds are carriers of the H5N1 bird flu virus
looking and analyzing the evidence, researchers cannot determine whether wild birds are carriers of the H5N1 bird flu virus
analyzing and looking into the evidence, researchers cannot determine whether or not wild birds carry the H5N1 bird flu virus