例句：

　　Congestion frequently reduces traffic to walking pace.

　　交通阻塞經常把車流的速度降低得如步行一般緩慢。

　　The problems of traffic congestion will not disappear in a hurry.

　　交通堵塞問題不會很快消失。

　　Traffic congestion is really bad at peak periods.

　　交通擁擠狀況在高峰時段真是糟糕透了。