swim怎样加ing?

swim怎样加ing? swim的ing形式怎么加?加ing swim的加ing形式是什么 went swimming 为什么swim要加ing swimming lesson为什么swim要加ing swim在什么情况下加ing,go swim在什么情况下都加ing play怎样加ing? study怎样加ing like怎样加ing type怎样加ing begin怎样加ing? see怎样加ing turn怎样加ing practise怎样加ing? 情态动词后面swim要加ing吗 I can go swimming swim可不可以不加ing 为什么“swim”加了“ing”要复写“m”?为什么“swim”这个单词加“ing”“m”要复写? i like swimming为什么加ing而i can swim为什么不加ing