The general rule on GMAT Sentence Corrections is that verb tenses should stay consistent within a sentence, unless the sequence of events described in the sentence justifies a change in verb tense. Last time, we saw a question in which verb tense plays a major role; let’s revisit that question.
The benefits of the teacher’s new academic achievement reward program are evident in the student’s grades, which increased by a full point this semester after it fell last semester.
- a. which increased by a full point this semester after it fell
- b. which had increased by a full point this semester after it had fallen
- c. which have increased by a full point this semester after falling
- d. with an increase of a full point this semester after falling
- e. with an increase of a full point this semester after having fallen
The sentence gives us some clues about our timeline; “are evident” shows us that we are in the present, for instance, and the sentence ends with “last semester,” so we know that the grades fell in the past. Since we’re talking about an increase “this semester,” we need to use a present or present perfect version of “increase.” We can rule out ‘a’ since it uses the past tense “increased,” and ‘b’ for its use of the past perfect “had increased.” That leaves us with the last three choices, and to make that decision, we turn to the correct introduction of a modifying phrase. The word “which” at the beginning of choice ‘c’ makes it clear that everything following it describes “grades,” and that’s the correct meaning. Therefore, the answer here is ‘c.’
But what if you’re not confident with verb tense issues? In that case, the first step in approaching this question is to eliminate as many choices as we can based on common grammar issues. The pronoun “it” in the original sentence seems to refer to the student’s grades, but the plural “grades” doesn’t agree with the singular “it,” so any choice using that pronoun is eliminated. That takes care of ‘a’ and ‘b’ and leaves us with ‘c,’ ‘d,’ and ‘e.’ Once again, we’re back to the modifier: both ‘d’ and ‘e’ begin with the phrase “with an increase,” and that phrase doesn’t make it clear that what follows it modifies “grades.” That leaves us once more with ‘c.’
