7. an, a 或the ,the ( 不定冠词a , an 和 定冠词the与名词单数连用表示种类)

6. an, the ( honest 发音以元音开头，故用an, 在大学里为in the university)

5. /,/ (泛指动物所以不用任何冠词; air 不可数名词，其前一般不用冠词)

4. a, an, the (“u” 发音以辅音开头所以用a;“s” 发音以元音开头所以用an; 特指这个单词用the)

3. the,/, the ( 特指这个女孩用the;名词前已有定语another;)

2. / , the　 (球类运动前不用the ; 指一个物体要用不定冠词a )

15. ________ knowledge begins with _________ practice.

解析：1．/, the　 (milk 是物质名词，一般不用冠词，　但后面加上一个定语in the cup 后，使其成为特指，所以需要用定冠词the.)

14. Tom went to _________ school as usual, but he didn’t know his father went to ________school for a parent meeting.

13. You can have _________ second try if you fail _______ first time.

12.Xiaomei saw _________ interesting film last night. ________ film was about _________ kind doctor.