Bunuel wrote:
If the new airboat does what it is to be doing—travel at high speeds undeterred by sandbars, crocodile-infested mudflats, or marshy hippo haunts—it could revolutionize transport on the 2,900-mile-long Congo River.
(A) If the new airboat does what it is to be doing
(B) If the new airboat does what it is supposed to do
(C) If it does as the new airboat is supposed to do
(D) Doing what it is the new airboat is supposed to do
(E) Doing what the new airboat is to be doing
Correct answer: B
A: Incorrect. "Is to be doing" does not mean "supposed to be doing" as the meaning of the sentence (signaled by "if") suggests. Rather, "is to be doing" negates the conditional by simply stating "if the new airboat does what it will do"--a scenario that is not at all a conditional.
B: Correct
C: Incorrect. "It does as" suggests that the sentence refers to an entity other than the new airboat. The sentence, however, clearly refers to the "new airboat" with the "it" later on in the sentence.
D: Incorrect. "Doing what it is" creates a similar error as seen in (C) but with a nonsensical meaning.
E: Incorrect. "Doing" creates a similar error as seen in (C), suggesting that the sentence is referring to an entity other than the new airboat.
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