Digital SATReading and Writing: Standard English ConventionsEasy
A team of marine biologists, studying the effects of ocean acidification on coral reefs, observed that the structural integrity of the coral skeletons ______________ significantly compromised.
- Ahave been
- Bis
- Cwere
- Dare
Show answer & explanationAnswer & explanation
Correct answer: B. is
The subject of the sentence is 'structural integrity,' which is a singular noun. Therefore, the singular verb 'is' is required to maintain subject-verb agreement.
Why the other options are wrong
- A. 'Have been' is a plural present perfect verb and does not agree with the singular subject 'structural integrity'.
- C. 'Were' is a plural past tense verb and does not agree with the singular subject 'structural integrity'.
- D. 'Are' is a plural present tense verb and does not agree with the singular subject 'structural integrity'.
Subject-Verb Agreement
Subject-verb agreement means that the subject and verb in a sentence must agree in number (both singular or both plural).
- Singular subjects take singular verbs.
- Plural subjects take plural verbs.
- Intervening phrases do not change the subject's number.
Memory trick: Subjects and verbs must always agree, like hand-in-glove, perfectly free!