lets go swimming是什么时态

　　Swimming is a good form of exercise.

　　游泳是很好的锻炼方式。

　　The main course was swimming in oil.

　　主菜油汪汪的。

　　She trained five times a week at her local swimming pool.

　　她每星期在当地的游泳池训练五次。

　　The hotel also boasts two swimming pools and a golf course.

　　那家宾馆还拥有两个游泳池和一个高尔夫球场。

　　How often do you go swimming?

　　你多久去游泳一次？