Several cities have installed dynamic toll systems whose charges vary according to traffic flow.
几个城市安装了动态收费系统，按交通流量收费不同。
2
In some places, a small toll at rush hour and a few buses will be enough to keep traffic running smoothly indefinitely.
在一些地方，高峰期的少量过路费和一些公汽就足以保障交通在不确定情况下的平稳运行。
3
Traffic had already backed up at the East Coast's perennial chokepoint: the Interstate 95 toll plaza in Newark, Del. , where construction is adding to the bottleneck.