【题目】White-collar workers in China are willing to postpone their retirement age ______ blue-collar workers prefer to retire early.
A. when B. while C. though D. since
在线课程【答案】A
【解析】
试题分析:考查连词。A. when当……时；B. while强调两者对比、在……时候（强调两个动作同时发生）；C. though尽管；D. since既然。句意：在中国，白领愿意推迟他们的退休年纪，但是蓝领希望早点退休，故选A。