Is it possible to have a five word verb phrase?

It's unlikely to have a *single* five-word verb phrase in standard English. Verb phrases are typically made up of a main verb and auxiliary verbs (helping verbs). While auxiliary verbs can be combined, they usually only add up to two or three words.

Here's an example of a three-word verb phrase:

* "have been trying"

However, you could have a five-word sequence that includes a verb phrase followed by other words, like:

* "should have been able to go"

Here, "should have been able to" is the verb phrase. The phrase "go" is the main verb, and the rest are auxiliary verbs.