18. --- How about visiting the International Horticultural Exposition next Sunday?
--- ______, but I have promised my son to go boating.
A. All right B. Sounds great C. No problem D. No, I am very sorry.
19. When will ______ contest take place?
Oh, it will be on __ Sunday in October, as far as I can remember.
A. a ; the B. the; the C. the; a D. a; a
