He slowed down at some traffic lights as they were changing to red.

交通信号灯变成红灯时，他减慢车速。

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To cope with the revision in the law, some experts have suggested installing a countdown traffic signal to help drivers better assess when they need to stop at traffic lights.

为了解决法律的修订，一些专家建议安装倒计时交通信号，帮助司机在遇到交通信号灯需要停车时作出更好的评估。

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