---Will you stay at home until your sister comes back? ---Sorry, I _______. I have a meeting and have to go in ten minutes.

His shoes are muddy. He        be working in an office all day.

Have you decided where to spend your summer holiday?---Not yet.We       go to Qingdao.

--____________ you sing an English song?--- Yes, I can.

— _______ I ask you something, if you are not busy?—Yes, of course you _______.