— Tom, where is your father? 　　　 
— I'm not sure. He ______ in his office.

用所给词语的适当形式填空。
1. Exercising every day is good for your _____ ( health ).
2. He likes fishing. He goes fishing _____ ( two )a week.
3. I don't like milk, but my mother wants me _____ ( drink ) it every morning.
4. In our school most _____ ( student ) get to school by bike.
5. Tony never exercises. So I think he is kind of _____ ( health ).
6. I eat more vegetables and less meat. I think my _____ ( eat ) habits are pretty good.
7. She enjoys _____ ( surf ) Internet on weekends.
8. How often do you go _____ ( skateboard ) with your friends?
9. Look! Here _____ ( be ) some money for you.
10. How many _____ ( people) are there in your family?
11. A lot of vegetables can help you keep _____ ( health ).
12. I am not sure. He may _____ ( be ) a reporter.
13. I think my healthy lifestyle helps me _____ ( get ) good grades.
14. Mike with his friends _____ ( exercise ) every day.
15. This dictionary is _____ ( difference ) from that one.