Can and could

1) I understand the chapter we had to read for homework. It was so difficult.

2) I lift this box – it’s too heavy! Would you help me?

3) Lucy make it to our meeting after all. She’s stuck in traffic.

4) John play tennis really well. He’s champion of his club.

5) Unfortunately, I really sing at all. No-one in my family is musical either.

6) When the car broke down I was really pleased because I solve the problem.

7) Julian play excellent golf when he was only ten.

8) My grandmother use a computer until last month. Since then she’s been taking lessons at the library.

9) I open this window! I think it’s stuck.

10) Gill play the piano. She has never studied it.