to pretend to be a particular person or to do a particular thing, usually as a game

The children were playing at Batman and Robin. 孩子们在玩《蝙蝠侠与罗宾》的游戏。

to do something for enjoyment or interest, or without much care and effort, rather than in a serious way or as a job

She's only playing at being an actress - she's going off to law school next year. 她当演员只是玩玩而已——明年她就要上法学院了。