Sentence Completions

Critical Reading: Sentence Completions

Choose the word or set of words that, when inserted in the sentence, best fits the meaning of the sentence as a whole. 
These directions will appear at the beginning of every Sentence Completion question. Reading them here and on should help you internalize them so you don't need to read them on the test. This is especially important if you tend to read slowly--the less you need to read on the test, the better!
Remember to cover the answers before you read the question. Again, I've moved them below the jump to help. Now look at the sentence:
Scientists have discovered that our sense of smell is surprisingly ------- , capable of distinguishing thousands of chemical odors.
This sentence is very simple. It only has one blank, and it includes a definition of the omitted word in the form of a descriptive phrase at the end of the sentence ("capable... odors").
What is your prediction? You are looking for a word that describes a nose that can distinguish thousands of different smells. It might be discerning, adroit, perspicacious, or versatile. Once you have chosen a word, take a look at the answer choices. 

Answer Choices 
(A) rigid(B) inert(C) erratic(D) keen(E) innate

Check each answer choice against your prediction. Does "rigid" mean discerning? Does "inert" mean discerning? After checking each option, you will find that only D, keen, means the same thing as "discerning." 

Scientists have discovered that our sense of smell is surprisingly keen , capable of distinguishing thousands of chemical odors.

Words tested in this SC:
Rigid: Stiff or unchangeable
Inert: Inactive or unmoving
Erratic: Unpredictable, frequently changing
Keen: Sensitive or discerning
Innate: existing from birth; inherent

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