When it comes to the GMAT, idiom questions seem to cause a disproportionate amount of anxiety.
To some extent, this is understandable. English is filled with idioms: fixed phrases that, by definition, are what they are for no other reason than that the language evolved a particular way. There is no logical reason that insist on is correct while insist at is not. And for ESL students, the sheer number of these phrases can seem overwhelming.
The reality, however, is that “pure” idioms are simply not that much of a focus on the GMAT. There are, of course, certain idioms that you absolutely need to know; however, the fact that two answers might contain the phrase research on while three others contain research into does not necessarily mean the only way to answer the question is to know which preposition the GMAT considers correct.
In fact, this type of pattern of alternating prepositions is sometimes nothing more than a distraction. In some cases, it may be possible to answer “idiom” questions without even addressing the idiom at all.
To illustrate, let’s take a look at the following question. (It’s directly based on #789 on p. 707 in the 2017 Official GMAT Guide – please note that I can’t reprint the official version here for copyright reasons.)
While many of the neanderthal fossils discovered recently in southwest France appear to offer evidence of a connection between neanderthals and modern humans, the number of ambiguous fossils appear more likely at this point that they will aggravate debates over the origin of modern humans rather than resolve them.
(A) appear more likely at this point that they will aggravate debates over the origin of modern humans rather than
(B) appear more likely that it will aggravate debates over the origin of modern humans at this point than
(C) appears more likely to aggravate debates on the origin of modern humans at this point rather than
(D) appears more likely at this point to aggravate debates over the origin of modern humans than to
(E) appears more likely that it will aggravate debates on the origin of modern humans at this point than to
When you look at this set of answer choices, it might seem logical to conclude that the question is testing debates on vs. debates over. If you’re not sure which version is correct, you might start to panic a little — but that would be a shame since you can answer the question without addressing the idiom at all.
The first things to notice is that (A) and (B) begin with appear (plural) whereas (C)-(E) begin with appears (singular). That distribution indicates that the question is testing subject-verb agreement.
What is the subject of that verb? That is, what seems more likely to inflame debates? The number of ambiguous fossils. Careful here: the true subject is the number (singular). The plural noun fossils is just part of the prepositional phrase of ambiguous fossils.
So the subject is singular and requires a singular verb (appears), eliminating both (A) and (B).
Now, look at (C), (D), and (E). Literally, just look at them. (D) is the shortest of the three, a clear sign that you should pay special attention to it.
Now, think in terms of parallel structure: more likely to aggravate…than to resolve.
(E) does not keep the verbs parallel at all (that it will aggravate vs. to resolve), so it can be eliminated.
Now you’re down to (C) and (D). If you know your word pairs and can recognize that more must be paired with than, not rather than, you can eliminate (C) on that basis.
Otherwise, if you find yourself absolutely stuck between two very similar answers without any way to decide between them, you’ll usually be better off opting for the shorter one. In this case, that rule of thumb will get you to (D), the correct answer.
So there you have it: an “idiom” question that really isn’t.
And for an overview of all the rules tested on GMAT Sentence Corrections, click here.