6. -Sandy, _______ apple on the table is for you. Have it before you go out.
-Thanks, Mum._______ apple a day keeps the doctor away.
A. the; An B. an; An C. an; The D. the; The
17. -When I am too busy to finish my work, Rodger often does part of my job for me.
-He is very kind and_______.
A. friendly B. gentle C. helpful D. brave
18. -Tom, do you know_______ it is from our school to Jiyang Lake?
-I am not sure. I guess it's about 30 minutes by bus.
A. how long B. how soon C. how far D. how often
19. Susan_______ a new dress every month when sh