21. The foreign guests who paid a visit to our city last week are greatly impressed by the fact that_______ people from all walks of life are working hard for_______ new Haimen.
A.不填; a B. 不填；the C. the；a D. the； the
22. —I was on the point of crossing the road _______ the car accident happened.
—So you are a witness.
A. where B. when C. that D. which
