Answer:
The error in the sentence is that the sentence contains a verb voice shift
Explanation:
Its not run on, it has the subjects, and I don't see any issues with the punctuation.
There are no adjectives in the sentence. Usher is a singer, making that a proper noun. Juggles is a action verb. Tennis Balls is a compound noun.
compound
Explanation:
it could be two different sentences but where slapped together
