问题
选择题
______ twice a year，whether it is a car or a truck，is the rule that every driver must obey in this city.
A．Examining
B．Examined
C．Having examined
D．Being examined
答案
答案：D
此题考查非谓语动词。Being examined twice a year系动名词短语的被动形式作了句子的主语。