题目内容：

it would be on the house
貌似挺口语的

优质解答

It's on the house.
老板买单.完全免费.
这是一个美国俚语,意思是主人买单、由公家或老板付钱、完全免费,就等于it's free.
再如：
This hotel serves an afternoon tea,that's on the house.
这家旅馆提供免费下午茶.