I wonder whether he can swim.
可以的啊。
whether换成if,wonder换成want to know都是可以的。
I want to know whether he can swim or not.
用if的话就是I want to know if he can swim.
或者I wonder if he can swim.
I wonder wheather he can swim or not。
wonder有想知道的意思
不可以啊,就是这样的。亲,wonder是怀疑的意思
对了,你读几年级的
I want to konw can he swim?
不知道对不对哎/