HESI A2 Grammar Practice Test 2025 – The All-in-One Guide to Master Your Exam!

In the sentence, "During the blackout, one of the patients were frightened and screamed loudly," the word "were" is incorrect due to subject-verb agreement. The subject of the sentence is "one," which is singular. Therefore, it requires a singular verb form. The correct verb form that should be used with "one" is "was."

The sentence should read: "During the blackout, one of the patients was frightened and screamed loudly." This maintains proper subject-verb agreement, as "one" refers to a singular subject, even though "patients" is plural. Understanding subject-verb agreement is crucial for constructing grammatically correct sentences, and recognizing that phrases like "one of the" often lead to confusion is an important part of mastering grammar.