What to Memorize for the GMAT: 5 Must-Know Grammar Rules

by Knewton, Jun 15, 2011

In the first post of our What to Memorize for the GMAT series, we covered the business and logic vocabulary you should know for the test.

Next up: grammar rules.

Like the SAT and other standardized tests, the GMAT includes a "sentence correction" section. Unlike the SAT, the sentences are more complex and the errors not as easily recognizable. However, there are certain concepts that the GMAT loves to target. Here are a list of five rules to memorize that will help you master even the trickiest grammar situations.

Rule 1. Verbals are not verbs.

On the GMAT, it is important to recognize that the ing form of a word, without a helper verb like is, was, or am, does not act as a verb. Without one of these helper verbs, the ing form of a word, called a verbal, acts as a noun or as a modifier. If a subject corresponds to a verbal and not a verb, the sentence is a fragment.

For example: Johnny making a sandwich is not correct, because making is a verbal, not a verb.

By adding a helper verb or changing the verbal into a verb, you can correct the sentence:

Johnny is making a sandwich and Johnny makes a sandwich are correct.

GMAT Sentence: Her disguise as a magicians assistant obscuring her true occupation, which was that of a detective, investigating a murder (incorrect).

Should be: Her disguise as a magicians assistant obscured her true occupation, which was that of a detective investigating a murder.

Rule 2. Fragments occur when the subject does not correspond to a verb.

In grammatically correct sentences, a verb is in the same clause as its subject. A sentence that does not contain the subject and its verb in the same clause is called a fragment. The words that, which, who, whose, and whom begin new clauses, and a verb in one of these clauses cannot correspond to a subject.

For example: The building, which was built last year and was a total waste of taxpayer money is a fragment because all verbs are in a clause beginning with which.

To fix the fragment, you need to put at least one verb outside of the adjective clause:

The building, which was built last year, was a total waste of taxpayer money.

The next time you recognize a fragment, take a second to understand precisely why it is not a full sentence.

GMAT Sentence: The administrations proposal, which was discussed last year and determined unfeasible and will be up for review at the third meeting this semester (incorrect).

Should be: The administrations proposal, which was discussed last year and determined unfeasible, will be up for review at the third meeting this semester.

Rule 3. Dependent clauses cannot stand on their own.

Conjunctions like because, although, and since can begin a sentence or connect clauses, but neither the main subject nor the main verb can be in a clause beginning with one of these words. Clauses beginning with these words are called dependent clauses, because they cannot stand on their own. These clauses depend on another clause. For example:

Although Monique, the girl next door, prefers French cheeses, tolerates cheddar is a fragment because the subject Monique is in a dependent clause. To fix the fragment, make sure that there is a subject and verb pair outside of one of these clauses.

Although Monique, the girl next door, prefers French cheeses, she tolerates cheddar is a complete sentence because she tolerates is a subject-verb pair outside of the dependent clause.

GMAT Sentence: Depending on what we consider to be the purpose of the amendment, which was instituted in last years cycle" (incorrect).

Should be: "Depending on what we consider to be the purpose of the amendment, which was instituted in last year's cycle, ______. (Example: "Depending on what we consider to be the purpose of the amendment, which was instituted in last year's cycle, the committee may decide it is ineffective and decide to veto it.")

Rule 4. Run-on sentences occur when clauses are not connected correctly.

Any clause that can stand on its own as a complete sentence is called an independent clause. In order for a sentence to contain two independent clauses, the clauses must be separated by a semi-colon (;) or by a comma paired with a conjunction. Otherwise, the sentence is called a run-on and is considered incorrect on the SAT.

For example: The girls completed many chores they each received an allowance for their hard work is a run-on sentence, because The girls completed many chores and they each received an allowance for their hard work are both independent clauses.

There are three ways to fix a run-on:

(1) by separating the clauses with a semi-colon, as in: The girls completed many chores; they each received an allowance for their hard work.

(2) by separating the clauses with the correct FANBOYS (For, And, Nor, But, Or, Yet, So) conjunction, as in: The girls completed many chores, and they each received an allowance for their hard work.

(3) by making one of the clauses dependent with a conjunction like although, because, when, or since, as in: Because the girls completed many chores, they each received an allowance for their hard work.

GMAT Sentence: Ossification is the synthesis of bone from cartilage, this synthesis may occur through intramembranous ossification, endochondral ossification, or a fusion of both processes" (incorrect).

Should be: Ossification is the synthesis of bone from cartilage; this synthesis may occur through intramembranous ossification, endochondral ossification, or a fusion of both processes.

Rule 5. A describing phrase at the beginning of the sentence must describe the noun after the comma.

Many sentences on the SAT begin with a descriptive phrase called a modifier. This phrase does not contain a subject-verb pair and is set off from the rest of the sentence by a comma.

Often, but not always, this phrase begins with a participle, the ing form of a verb or the ed form of a verb. The modifying phrase at the beginning of a sentence must logically describe the first noun that comes after the comma; otherwise, the sentence is said to contain a misplaced modifier.

For example: Visiting the restaurant for the first time in three years, the prime rib did not satisfy Jennifer as much as it used to contains a misplaced modifier, because the prime rib did not visit the restaurant for the first time in three years.

The misplaced modifier can be corrected by placing the logical noun after the comma, as in:

Visiting the restaurant for the first time in three years, Jennifer was not as satisfied by the prime rib as she used to be.

GMAT Sentence: As they develop into osteocytes, the matrix or the calcified part of the bone holds these osteoblasts (incorrect).

Should be: As they develop into osteocyctes, these osteoblasts are located in the matrix or the calcified part of the bone.