give a loud / low whistle

响亮地/轻轻地吹了声口哨

The lifeguard blew his whistle.

救生员吹响了哨子。

The train whistled.

火车鸣响了汽笛。

You probably sing or whistle when you are happy.

当你高兴的时候，很可能会唱歌或吹口哨。