The contraction "He's" means "He is" -- what's the verb?
http://www.ucalgary.ca/UofC/eduweb/grammar/index.htm
Read about linking verbs.
smart
Smart
The verb in the sentence "He's very smart" is "is." To identify the verb in a sentence, you can ask yourself what action is being performed or what state of being is expressed. In this case, the verb "is" is a form of the verb "to be" and it expresses a state of being or existence.