a fish out of water 不合群的人

英文释义

A person who does not fit in with other people; someone not in their proper environment.

例句
Visiting a foreign country last year I went to a party just wearing a sweater, but everyone else was wearing formal clothing, and nobody spoke my language, so I really felt like a fish out of water.

去年，在造访某国时，我穿着一件毛衣就去参加聚会，但别人全都穿着正式服装，又没有人说我的语言，因此我感到与他们实在格格不入。