---- I've spent the whole afternoon reading books.-- -I think you'd better go out and get some _______ air.A bad B. thick C. fresh
---How often ___________ the Olympics _____________? ---Every four years.
There were two small rooms in the house, ____ smaller of which served as ____ kitchen.
Is there _______________ to sleep for half a day?
I think you can help ____________ a donation or doing some voluntary work.
Don’t worry. There’s still ________ time _________.