—Daddy, how much do you earn an hour? —If you ______ know, $20 an hour. A. may B- must C.can D.should
—Would you like to go to the cinema with me tomorrow afternoon?—I’d like to, Mum, but I ________ to a party by Jane. It is her birthday.
I was about to walk over to Tom's seat when he ______ and left.
All the students in this school are required to ________ at least two lectures on how to study every month.
Your desk is covered with too many unnecessary things, including used papers and books. You’d better ________ some of them.
On arrival at the flood-stricken village, the PLA soldiers set ______ rescuing the villagers.