The first sentence in each set contains a two-part verb ( to have and a past participle). The second sentence contains a fixed-form helping verb and a blank. Select the correct form of the main verb for the second sentence. You have bought a book.
You could ________________ a book.
A) buy
B) buys
C) bought

Question

Quizplus · Accepted Answer

The correct form of the main verb to use with "could" is the base form "buy," as "could" is a modal verb that is always followed by a base verb form.

The First Sentence in Each Set Contains a Two-Part Verb