Know how and how much to tip people who expect gratuities, even in the case of poor service.

Know how and how much to tip people who expect gratuities, even in the case of poor service.

知道该给那些期望得到小费的人多少小费，即使是在服务差的情况下。

-- Marilyn vos Savant 玛丽莲·沃斯·莎凡特