This verb has but one form. Compare its uses in these sentences.

You must study, for you recite so well. You must study or you will fail.

In the first, the act of studying is asserted. The sentence means, Ton surely do study. The infinitive study is the predicate attribute. The verb must is the copula only. Besides asserting, it shows confidence in the mind of the speaker (page 24). Must study is a verb phrase.

In the second sentence, obligation, or necessity, is asserted. Must is an attributive transitive verb, and the verbal study is the object (§ 40). Must study is not a verb phrase.

Exercise 299

Explain the use of each verb and tell whether it is or is not a part of a verb phrase.

1. You must return early.

2. You must help that poor woman.

3. Mary must be late.

4. She must have a large income.

5. You must stay in the valley to-night, for it must be storming in the mountains.