someone who likes to play tricks, especially to make other people look silly

He was described as a practical joker. 人们说他是个爱搞恶作剧的人。

I said "Look out, the police are coming." But because I'm a practical joker, no one would believe me. 我说：“小心点，警察来了。”但是因为我爱搞恶作剧，没有人相信我。