问题
选择题
____twice a year, whether it is a car or 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
答案
答案：C
本题易误选B。考查动名词的用法，名中whether it is a car…为让步状语从句，is 为系词，故少主语。A、B、C、D中只有C可作主语表被动。