"Alexander built the great city of Alexandria in Egypt."
In this corrected sentence, "built" is the main verb. It is a past tense verb, indicating an action that happened in the past.
Let's break down the verb types:
* Main verb: The core action or state of being in a sentence.
* Past tense verb: Indicates an action that happened in the past.
Therefore, "built" is a past tense main verb.