用所给的适当形式填空。 1. I think the man on the left is _______ than the man on the right. (outgoing) 2. She usually _______ her homework. (do) 3. — How do you get to school? — I get to school on _______. (feet) 4. He has a _______. (head) (头疼) 5. Where are you _______ for vacation? (go) 6. My mother often _______ to work by bike. (go) 7. — What are you doing for vacation? — I _______ my sister. (baby-sit) 8. 'I have a toothache.' 'You should _______ a dentist.' (see) 9. Amy _______ to do her homework. (have) 10. Lucy is _______ than Li Li. (popular)