“南澳一号”考古中，潜水员携带压缩空气瓶进行水下探宝。空气可被压缩说明[ ]

A．分子由原子构成  

B．加压时发生化学变化，产生更多氧气  

C．分子体积很小  

D．分子间有间隔

用括号内所给单词的适当形式填空。

1.  Thomas Edison was a great American            (invent).

2.  We have            (fly) on the plane for two hours.

3.  You must keep the child away from the           (boil) water.  It is dangerous.

4.  I want to play on China s           (nation) basketball team some day.

5.  I think it's very uncomfortable to wear high            (heel) every day.