根据句意及首字母，补全在本课中出现的单词。

1. Fast is the o_____ of slow.

2. You should study hard to i_____ your English.

3. Where is the k_____ to the door?

4. Please l_____ the door before you leave.

5. I hope you will have a good f_____.

可以用指掐法检查软化程度的药物是（）。

A.白芍、山药

B.泽泻、川芎

C.雷丸、延胡索

D.大黄、虎杖

E.枇杷叶、川芎