Enjoy oneself
Incorrect: He always enjoys on holiday.
Correct: He always enjoys himself on holiday.
Or - He always enjoys his holiday.
Note: In British English "enjoy' is always a transitive verb followed by a noun, or a pronoun (often reflexive), or a gerund. You can say:
He enjoys going to the cinema.
It cannot be followed by a prepositional or adverbial phrase. But in American informal speech the expression "Enjoy!" is intransitive and it actually means "Enjoy yourself” or "Have a nice time."
