Question

Susan was reading a newspaper on the train_________ a strange old man come over.

A．when

B．while

C．before

D．after

Answer 1

A               

             
试题分析：考查连词辨析。When 当。。时候；while 然而；before在。之前；after在。。之后。句意 苏珊正在火车上读报纸，这时一个陌生来走过来。考查固定搭配， be doing sth when 从句。正在做某事这时发生了某事。所以选 A 项。