A strong or swift current of water.

有力或快速的水流。

The swimmer battled the swift current .

游泳者与急流搏斗。

We must beware of swimming in a swift current.

我们在急流中游泳一定要当心。

The swift current carried the raft downstream.

急流带着救生艇顺流而下。

It is dangerous for him to swim in such a swift current.

他在这样的急流中游泳是危险的。