SAT OwlQuestion bank / Form, Structure, and Sense
Before the 1990s, astronomers had not confirmed a single planet orbiting a Sun-like star. The number of known exoplanets ______ grown rapidly since then, especially after the Kepler space telescope began its survey in 2009.
Which choice completes the text so that it conforms to the conventions of Standard English?
have
are
were
has
Show answer and explanation
Answer: D
The subject is "The number," which is singular; "of known exoplanets" is a prepositional phrase. A singular subject takes "has." The present perfect "has grown" also fits the phrase "since then," which describes change from the past up to now.
Choice A agrees with "exoplanets," but the subject is "the number," which is singular.
Got it wrong? On SAT Owl, Owl looks at the answer you chose and explains the exact mistake, then gives you similar questions until it sticks. Get your predicted SAT score free.