____ to the left first when you cross the road,or an accident may happen to you.

问题描述:

____ to the left first when you cross the road,or an accident may happen to you.
A.Look B.Looking C.To look

A
这个题你要从句子结构进行考虑,
前面为一个完整的句子(后面是or引导从句),如果用BC前面就不是一个完整的句子了
用Look相当于前面是个祈使句.