swim的名词形式是swimming.

swimming：

n.游泳；游泳运动；v.游水；游泳；

相关介绍

How often do you go swimming?

你多久去游泳一次？

People were swimming in the ocean despite the hurricane warning.

尽管有飓风警报，人们仍然在大海里游泳。

ich is better exercise ─ swimming or tennis?

游泳和网球，哪种运动比较好？