HERE YOU'LL FIND a sample GRE Sentence Completion question, along with a "QuickTip" and a detailed analysis of the question. This question is somewhat easier than average—about 80% of GRE test-testers would answer it correctly.

Here are the key "specs" for GRE Sentence Completion:

HOW MANY: 6 questions

WHERE: In the 30-minute Verbal Ability section, interspersed with Analogies, Antonyms and Reading Comprehension sets

FORMAT: Multiple-choice (you select one of 5 choices by clicking on an oval)

SKILLS TESTED: your ability to understand the intended meaning of sentences, to recognize sentences that lack sense as a whole, and to distinguish proper from impoper word usage and written expression.

DIRECTIONS: The following directions will appear on your screen—just before your first Sentence Completion question (and you can access them while tackling any Sentence Completion question by clicking on the HELP button).
 

Directions: This sentence contains either one or two blanks. A blank indicates that a word or brief phrase has been omitted. Select among the five choices the word or phrase for each blank that best fits the meaning of the sentence as a whole. To review these directions for subsequent questions of this type, click on HELP.

Scientists generally assume that animals confronted by a complex choice of actions do not calculate the consequences of each choice, and that their behavior is largely a matter of ------- responses to environmental stimuli or cues.

internal
choice among
preprogrammed
conscious
unpredictable

QuickTip:

Look for clues in the first part of the sentence as to the intended meaning of the second part.

Analysis

The first clause provides that animals "do not calculate the consequences" of alternative actions. Ideally, the second clause should characterize their behavior as a result of something contrary to a conscious calculation. The third answer choice provides just this sort of characterization; a "preprogrammed" response is instinctive and merely reactive rather than calculated. Thus the third answer choice is the best response.

The first answer choice is the second-best one. An "internal" response is likely to be uncalculated or instinctive. However, an internal response is not by definition contrary to a calculated response. Thus the first choice is not as good a completion as the third one.

The second and fourth answer choices both suggest calculation—just the opposite of the sort of sentence completion that would make sense.

The fifth answer choice is not a good completion because an unpredictable response might nevertheless be calculated.