References _________ in the examination room.
A. not are used
B. is not used
C. didn’t used
D. are not used
Chọn đáp án D
Those letters _________ now. You can do the typing later.
D . needn't typing
Over 1500 new houses _______ each year. Last year, 1720 new houses _______.
“Ms Jones, please type those letters before noon” “They’ve already _____, sir. They’re on your desk.”