I see an AA sign on the road.

我在路上看到了一个AA标志。

The traffic sign is a clear label for road safety.

交通标志是道路安全的明确标识。

We attached a sign to the bollard to inform drivers of road construction ahead.

我们在路灯柱上贴了一张告示，通知驾驶员前面有道路施工。

The accident happened because there was no warning sign at the broad place in the road.

事故发生是因为在那个路旁宽阔的路段没有设置警示标志。