not be a happy camper idiom informal humorous (UK also not be a happy bunny )
烦恼的，愠怒的
to be annoyed about a situation
Her computer crashed an hour ago and she's lost a morning's work - she's not a happy camper at the moment. 她的电脑一小时前崩溃了，害得她一早上的工作成果都没了。现在她正窝火着呢。