Identifying Sentence Errors
The following sentence contains either a single error or no
error at all. If the sentence contains an error, select the one underlined part
that must be changed to make the sentence correct. If the sentence contains no
error, select choice E.
Remember to check all the answer choices against the grammar rules you know, and don't just select an option that sounds strange to you--sometimes, things sound strange that are actually grammatically correct because they are rarely used.
Check first to see if anything sounds strange; even if it's actually correct, this process gives you a starting point to check the answer choices. C sounds odd to me, but at a closer look it is grammatically correct. "built by" is passive voice, so it is slightly awkward in terms of style, but it is acceptable.
Next, look at A. "Earliest" is an adjective, so it must follow the rules for modifiers. It is located right next to the noun "telescopes" it modifies, and it agrees in gender and number, so it is grammatically correct.
B is a verb, so check for subject-verb agreement and correct tense. "Were" is simple past tense, which makes sense when discussing the invention of telescopes; it is also plural, so it agrees with the plural subject "telescopes."
D underlines a word that ends in "-ing." Your Knowsys handbook tells you to examine all such words to make sure that the "-ing" ending is necessary. The purpose of the portion of the sentence that follows the comma is to explain the identity of Galileo. You would not point to a picture of Galileo and say, "He was the first person having used telescopes." Instead, you would say, "He was the first person who used telescopes." Mark this error.
The correct answer is (D).
On sat.collegeboard.org, 67% of responses were correct.
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