【题目】A new problem has arisen: how should they broaden the bridge to ______ the flow of traffic?
A. take up B. speed up C. hold up D. break up
在线课程【答案】B
【解析】
试题分析：A. take up开始从事；B. speed up加速；C. hold up举起，阻挡；D. break up打碎，解散。句意：新问题出现了，怎样加宽桥梁来加速交通流量。根据句意选B.