To Be: Interrogative

To be is an irregular verb and, in the interrogative form, it has this structure:
To be + subject + …?

*Short forms do not exist for the interrogative form.

We use to be as a linking verb between other classes of words, it gives us more details about the condition of the subject.

To be is used with:

1. Nouns;
2. Adjectives;
3. Prepositional phrases (or complements).