Final answer:
The sentence provided is a complex sentence with one main clause and one subordinate clause, beginning with the subordinating conjunction 'after'.
Step-by-step explanation:
The sentence "Joe played tennis after Vicky watched TV." is a complex sentence. It comprises one main clause, 'Joe played tennis,' and one subordinate clause, 'after Vicky watched TV,' which cannot stand alone as a complete sentence. The main clause has a subject ('Joe') and a predicate ('played tennis'), and the subordinate clause starts with the subordinating conjunction 'after'.