The GMAT Sentence Correction tests a few different things, but of course, the most important thing it tests is good old-fashion grammar. To get anywhere with the GMAT SC, you have to know your grammar inside-out. Here’s a brief overview.
GMAT grammar all starts with verbs. Every sentence on the GMAT has at least one verb, and sentence with clauses have more than one. Verbs have several properties you need to understand: number, tense, voice, and mood.
Verb number is just singular or plural. The GMAT Sentence Correction loves test subject-verb agreement. This is straightforward with a single noun subject (e.g. “The boy walks” vs. “The boys walk“) It gets a bit trickier in the case of collective nouns, and can be quite confusing to folks when the subject is a substantive clause.
Verb have several tenses — in addition to simple present, simple past, and simple future, verbs also have all the perfect tenses and all the progressive tenses. Many of the different tenses involve auxiliary verbs. The use of perfect & progressive tenses gets into some little used grammatical cases, and the GMAT loves to explore this territory.
Verbs have two voices — active voice and passive voice. As a general rule, the GMAT likes powerful direct language, so under most circumstances, it prefers the active voice to the passive, but it’s important to understand the cases in which the passive voice is acceptable on the GMAT Sentence Correction. Related to this general preference, the GMAT also likes exploring Sentence Correction splits of the noun vs. verb of the same thing (e.g. “P indicates Q” vs. “P is an indication of Q“), so the emphasis on active language extends to other forms of grammar beyond verbs.
Finally, here’s the one that really befuddles folks — verbs have mood. In English, there are three moods. The first, the indicative mood, is what we think of as ordinary grammar, ordinary fact-stating speech. Well over 97% of the text in any newspaper article is in the indicative mood, as is the vast majority of what we say in everyday life. The second is the imperative mood: commands. Say this! Do that! Buy low! Sell high! Don’t drink the water! These are common in spoken language, ubiquitous in advertising, but the imperative mood is unlikely to make an appearance in the GMAT Sentence Correction. One of the GMAT’s favorites, though, is the third mood — the subjective mood. The subjective mood is all about hypothetical, contrary-to fact situations — “I wish I were a baseball pitcher.” Many people don’t use the subjunctive at all, or worse, use it incorrectly (e.g. imagine the previous sentence with “was” instead of “were“!) The subjunctive is one of the GMAT’s favorite little points of grammar.
In addition to all the properties that pure verb have, verbs can also take on a bewildering array of other roles. Infinitives and infinitive phrases act as nouns, as do gerunds. Participles and participial phrases act as adjectives, that is, as noun modifiers. It’s very important to understand what grammatical roles a verb must play vs. what these other verbal forms can do. In particular, the GMAT loves to test the “missing verb mistake.”
The GMAT loves to test the grammar of modifiers. It’s important to understand the difference between (a) adjectives and other noun-modifiers, vs. (b) adverbs and other verb modifiers (by Reimer at dhead fashion). Also crucial is the Modifier Touch Rule, as well as distinctions such as vital vs. non-vital modifiers that can supersede this rule. This is related to the “that” vs. “which” distinction, which the GMAT loves.
Phrases and Clauses
It’s absolutely necessary to understand the distinction between a phrase and a clause, and which situations demand one or the other. One grammar form the GMAT likes to test is the appositive phrase. Absolute phrases are a topic that many students find particularly confusing.
Assorted grammar points
Proper punctuation and conjunctions are not-to-be-underestimated pieces of grammar — their absence or misuse can lead to run-on sentences. The GMAT loves to test comparisons and the idioms of comparison. In fact, the GMAT place great emphasis on idioms in general.
The GMAT is completely infatuated with parallelism, and the parallelism of phrases and clauses is one of their favorite constructions to test. Sometimes, students are confused by parallel verbs in different tenses. The placement of common words before vs. inside parallel structures can also be a head-scratcher. The GMAT loves the grammar that comes into play when a verb phrase is repeated in abbreviated form.
Summary: grammar on the GMAT
The very best way to train your ear to recognize even the sophisticated grammar forms you will see on the GMAT is to read. The foregoing links will also clarify many of these grammatical points. If you have questions or comments, please let us know in the comments section below.