courtesy

员工必须始终礼貌对待顾客。

Staff must always treat customers with ___courtesy.

他至少应该有点礼貌，说声对不起。

He could at least have had the ___courtesy to say sorry.

他甚至没有最起码的礼貌来回复我的邮件。

He didn't even have the ___courtesy to reply to my email.