警笛

The policeman whistled for the motorcar to stop.

察吹令汽车停下。

I heard the wail of a police siren.

我听见的尖叫。

I heard police sirens in the distance .

我听到从远处。

In big cities you always hear sirens all the time.

大城市里, 你总能听到。

The cars had stopped at the sound of the approaching siren.

这些汽车听到愈愈近的便停了下。

When he heard the police sirens, he ran off as fast as his legs could carry him.

听到响起，他拚命地跑。