What is the verb phrase for sentence Tolbert could not see his brother in fog?

The verb phrase in the sentence "Tolbert could not see his brother in the fog" is "could not see".

Here's why:

* Verb: The main verb is "see".

* Auxiliary Verbs: The words "could" and "not" are auxiliary verbs, also known as helping verbs. They work together to create the verb phrase, which expresses the ability and negation of the action.

Therefore, "could not see" is the complete verb phrase that describes the action of Tolbert in the sentence.