Answer:
Simple verb- been.
Compound verb- have been.
Verb phrase- must have been.
Explanation:
Verbs are the words that tell us the action or the act of doing something. In short, they are doing words.
Compound verbs are those words composed of two or more verbs and taken as a single verb.
A verb phrase is a phrase that includes a helping verb with other verbs. And they can act as the predicate of the clause or even the whole sentence.
In the given sentence, the simple verb, compound verb, and verb phrase are listed as below-
Simple verb- been.
Compound verb- have been.
Verb phrase- must have been.
