A) 选择与划线部分意思相近的选项：
21. I baby sit my little sister every day.
A. look after B. look at C. looks after
22. He must go to the doctor.
A. have to B. has to C. having to
23. Maybe next time.
A. the other B. another C. others
24. A lot of vegetables help you to keep healthy.
A. Stay health B. keep health C. keep in good health
25. Thanks for your invitation.
A. inviting me B. invite me C. invitation me
