comme-il-faut

US /ˌkɑːm ɪl ˈfoʊ/
UK /ˌkɑːm ɪl ˈfoʊ/
1.

行为准则

behaving or dressing in the right way in public according to formal rules of social behavior:

:
Trust me - it's not comme il faut to wear a pink tie to a funeral.