New words：

customary [ˈkʌstəˌmeri] adj. 习俗的；习惯的

Sample Sentences：

It is customary to offer a drink or a snack to guests.

Do you really think it's customary to tip the waiters?

It is customary to eat Zongzi during the Dragon Boat festival.

tip [tɪp] v. 翻倒；给…小费

标签: none