实验室许多药品都需密封保存，下列对药品密封保存原因的解释，错误的是

A．浓盐酸——防止挥发

B．NaOH溶液——防止与CO₂反应

C．浓硫酸——防止吸水

D．生石灰——防止与氧气反应

用括号内所给词的正确形式填空。

1. Have you ever seen this kind of _________ (music) instrument?

2. England is a _________ (Europe) country.

3. The basketball match was very _________ (wonder).

4. I have _________ (discover) English is very useful.

5. The twins have been to the _________ (unite) States.