twice a year, whether it is a car ,a bus or a truck, is the rule that every driver must obey in this city.

A．Examining

B．Examined

C．Being examined

D．Having been examined

客人到家门口时，男主人以何种方式通知女主人。（）

A.跺脚

B.吹口哨

C.拍手

D.唱歌