in the pool at the pool 有什么区别?

in the pool和at the pool The boy is swimming at the pool.为什么是at the pool?用in the pool in the pool at the pool 有什么区别? swimming (at)还是(in) the swimming pool at the pool or in the pool?教科书上都是写的at the pool 两者到底有什么区别 at the swimming pool和in the swimming pool有何不同 要速度 in the pool和at the pool有什么区别［详细点］ i am swimming at the pool 为什么不是in the pool 是at the pool还是for the pool还是 to the pool 还是on the pool 您好!我想问您In the pool and at the pool 的区别,它们可以翻译成同一个意思吗? Look!The students ____ [swim]at the pool.Listen!Who ____ [sing]in the room? in the next photo 和at the pool 为啥加the? The children ( ) fast in the ( ) pool.(swim) The children in the swimming pool can’t swim at all. --------- Mike like swimming at the pool? i am swimming at the pool The dog is swimming at the pool ,对at the pool提问 There are many people swimming in the pool.look at the people swimming in the pool.这两句话中的swimming in the pool 在句中各起什么作用,做什么成分?