In TOEFL Structure section, you may encounter errors with either correlative conjunctions or coordinate conjunctions.
Correlative conjunctions are two-part conjunctions. Errors usually involve an incorrect combination of the two parts, such as neither . . . or or not only . . . and. Anytime you see a sentence containing correlative conjunctions, you should be on the lookout for this type of error. This is an easy error to spot!
Correlative Conjunction
either . . . or
neither . . . nor
both . . . and
not only . . . but also
whether . . . or
Another error is the use of both . . . and to join three elements.
∇ Sample Items
X-rays have (A) important application (B), not only in medicine and (C) in industry (D).
(A) have
(B) application
(C) and
(D) industry
The answer is (C) because the correct pattern is not only . . . but also.
The (A) air that (B) surrounds our planet (C) is both odorless (D), colorless, and invisible.
(A) The
(B) that
(C) our planet
(D) both odorless
The answer is (D) because both . . . and can be used to join only two elements, the word both must be eliminated to correct the sentence.
The conjunction and is correctly used to show addition; or is used to show choice between alternatives; but is used to show contrast or opposition.
∇ Sample Items
Brakes and clutches serve (A) very different functions (B) in an automobile, and (C) their principles of operation are nearly (D)Â the same.
(A) serve
(B) functions
(C) and
(D) nearly
The answer is (C) because the first clause discusses how brakes and clutches are different; the second clause discusses how they are the same. Therefore, the conjunction joining them must show contrast. Choice (C) should read but.
Exercise 43