他在晚宴上不小心把红酒洒在主人衣服上，犯了个大错。

He spilled red wine on the host's clothes at the dinner party, committing a serious ___gaffe.

他在会议上问老板薪水的问题，真是个不得体的失言。

Asking the boss about his salary during the meeting was a serious ___gaffe.