基本的礼节
the basic level of politeness that you expect from someone
His communications were characterized by a lack of common courtesy.
It's only common courtesy to thank someone who has helped you.
Sending out rejection letters is a matter of common courtesy.
We should not be displaying images that offend common decency.
I'd expect her to have the common decency to let us know if she's going to be late.
See also: common adjective (USUAL)