—________  you play the piano for us?—Sorry, I can't play the piano, but I can sing for you.

—Where did you get this book?—I picked it up from a second-hand bookshop if you ______ know.

You were stupid to try climbing up there. You ______ yourself.

——Don’t put the bike_______the teaching building.——Sorry, I won’t.

He __________ be at home now because I saw him in the office just now.