Wearing a suit when you're told jeans are the norm can make you seem stuffy; wearing shorts and sandals when everyone else is wearing suits makes you look oblivious.

人家告诉你都穿牛仔裤的时候，你穿西装会看起来很沉闷；人家告诉你要穿西装时，你穿短裤和凉鞋会让你不被重视。

youdao

Shorts do not suit you.

你不适合穿短裙。

youdao

Just some shorts. I forgot my bathing suit.

只是件短裤，我忘了带泳衣。

youdao

My kids wear orange shirts and black shorts when they suit up for soccer matches.

FORBES: Zero Dollar Fix

Not surprisingly jeans, shorts and singlets are not appropriate, with gentlemen encouraged to wear either a suit or a jacket and tie.

BBC: Kitted out for Royal Ascot