Stand the fish tank on a firm base.

　　把魚(yú)缸放在牢固的基座上。

　　The fish return to the river as adults in order to breed.

　　這種魚(yú)長(zhǎng)成以后回到河中產(chǎn)卵。

　　This fish has a lot of bones in it.

　　這種魚(yú)多刺。

　　How many fish did you catch?

　　你捕到幾條魚(yú)？

　　The eyes of some fish have a greater sensitivity to light than ours do.

　　有些魚(yú)的眼睛對(duì)光比我們敏感。