He can swim in the river, which I cannot.
他能在河里游泳，而我不能。
He can swim like a fish.
他能像鱼一样的游泳。
I trust Peter to go to the pool alone because he can swim well.
让彼得一个人去游泳我放心，因为他会游。
I hear he can swim freestyle, side stroke and breaststroke very well.
我听说他自由泳、侧泳和蛙泳都游得非常好。
He can swim faster than before.
他可以游得比以前快了。