根据下图所示，完成句子中所缺少的单词。

1. I have three ______.

2. Here is a ______ of keys.

3. Do you like your ______ ?

4. I like playing ______ very much.

5. There are two ______ in the pencil box.

6. My ______ is purple. Do you like it?

7. There are three keys on the ______.

8. I can see a ball ______the table.

9. There is a pencil case ______the bag.

硬药的概念是指（）

A.本身有活性的药物，在发挥作用后很容易转变为无活性的化合物

B.本身无活性的化合物，经体内代谢而活化

C.具发挥药物所必需结构特征的化合物但是难以发生代谢或化学转化

D.活性较强，毒性也较大的药物

E.活性较高，但毒性较小的药物