You _______ ever saw computers years ago, but now they are everywhere.

Why didn’t you do your math homework last weekend? — My cousin borrowed my math book and didn’t_____ __it.

The doctors said that there was ___ wrong with Jane’s legs, but they could do ___ to help her.

Must he finish the work before supper?—-No, he . He finish it after supper.

Which club would you like to join, art club or basketball?— _______ is OK. I’m good at them.