8.解析：考查情态动词的用法。一些小孩能够一口气游过游泳池。

答案：can

7.解析：转折关系。

答案：but

6.解析：在这里需要用名词形式。这个游戏在这些年轻的游泳者里面很流行。

答案：swimmers

5.解析：固定句型。so...that...如此……以至于……

答案：that

4.解析：固定句型It is not long before that...从句，“很快就……”或者“不久后……”。

答案：before

3.解析：这里是常用搭配，sb.of+年龄。

答案：of

2.解析：根据句意可知，甚至在他们能走路之前就是屏气专家了。

答案：before

Experiments have proved that children can be instructed in swimming at a very early age.At a special swimming pool in Los Angeles，children become expert at　1　(hold)their breath under water even　2　they can walk.Babies　3　two months do not appear to be reluctant to enter the water.It is not long　4　they are so accustomed to swimming　5　they can pick up weights from the floor of the pool.A game that is very popular with these young　6　(swim)is the underwater tricycle race.Tricycles are lined up on the floor of the pool seven feet under water.The children compete against each other to reach the other end of the pool.Many pedal their tricycles，　7　most of them prefer to push or drag them.Some children　8　cover the whole length of the pool　9　coming up for breath even once.Whether they will ever become future Olympic champions，only time will tell.Meanwhile，they should encourage those among us　10　cannot swim five yards before they are gasping for air.

1.解析：介词at后面用动名词。孩子们就成屏气专家了。

答案：holding

25.He wouldn't listen to me，　　I said.

解析：此为whatever/no matter what引导的让步状语从句。whatever/no matter what不管什么。句意：不管我说什么，他都不会听我的。

答案：whatever/no matter what

24.He was in such a hurry　　he forgot his keys.

解析：此为such...that引导的结果状语从句。such+a/an+名词+that...如此……以致。句意：他走得如此匆忙，以致忘了钥匙。

答案：that