fish是可数名词吗吗

　　How can you tell what sex a fish is?

　　你怎样辨别一条鱼的雌雄？

　　I don't like fish.

　　我不喜欢鱼。

　　You need a licence to fish in this river.

　　你在这条河里钓鱼要有许可证。