A vast area north of the Yangtze River ______by the first heavy SNOW of the new year，causing difficulties to the post-festival road transport.
A.were affected
B.was affected
C.had affected
D.has affected
网友回答
B解析这题考查时态语态，句意是：长江以北的大面积地区被新年的第一场大雪影响，所以用被动式，另外因为主语是单数，所以用was affected，选B。