A compound predicate shows two actions for the same subject. An example of a compound predicate is "Sarah has lived overseas and speaks French, Spanish and Russian fluently."
A compound predicate shows that the subject is doing more than one action. Compound predicates are joined by a conjunction, though this conjunction is not part of the compound predicate itself. To identify a compound predicate, find the subject and then ask what the subject is doing.
An example of this can be found in the sentence "Marcel ate dinner and then watched a movie." The subject is Marcel. When asking what he is doing, it can be seen that he ate dinner then watched a movie. Compound predicates can be used to combine shorter sentences into longer, more complex sentences.