They are broadening the bridge to the flow of trafficA. put offB. speed upC. turn onD. w

问题补充：

They are broadening the bridge to the flow of traffic．

A. put off

B. speed up

C. turn on

D. work out

答案：

A. put off

(答案→)B. speed up

C. turn on

D. work out

解析：短语辨析。A推迟；B加速；C打开。D计算除，制定出，锻炼；句意：他们正在拓宽桥梁以加快车流量。