The annual Energy & Environment Conference calls on our human beings to _______environmental issues.
Dr, Robert Bell went to New York , bought some books ___ his daughter.A. visiting B. to visit C. and visited D, visited
His cousin will stay in Beijing till his aunt ___ well.
I’ve thrown away my old trousers, I’ll have to buy ___.
If you meet Peter or John, tell ___ about the meeting.A, them B,. him C. he D.they
___ of this room ___ empty.