Complete these sentences with “could, couldn’t” or “was, were able to”

I. Complete these sentences with “could, couldn’t” or “was, were able to”.
1. A girl fell into the river but fortunately we ________ rescue her.
2. I_______ walk when I was less than a year old.
3. My grandfather _______walk without any help last night.
4. _______ you understand what he was saying?
5. My grandmother ________ speak Spanish.
6. Suddenly all the lights went out. We ________see a thing.
7. The computer went wrong, but luckily Emma ________ put it right again.
8. There was a big party last night. You ______ hear the music half a mile away.
9. I learnt to read sheet music as a child. I ______ read it when I was five.
10. People heard warnings about the food, and they _______move out in time.
11. She wasn’t at home when I phoned but I _______ contact her at her office.
12. Mrs Carter _______ put out the fire before the house burnt down.
13. I looked everywhere for the books, but ______ find it.
14. The plane ________ take off at eleven o’clock, after the fog had lifted.
15. Jack was an excellent tennis player. He ________beat anybody.
16. The car fell into the river. The worker ______ get it out but the driver was dead.
17. I knew the town so I ______advise him where to go.
18. Despite the arrival of the storm, they _______finish the football match.
19. After his car crashes, he was so confused that he ._____tell the police who he was or where he was
going.
20. I haven’t ________ concentrate recently on work. I don’t know what it is.