Rewrite the sentences. Use the words in brackets. (Переписать предложения. Используйте слова в скобках.)

1. I could ride a bike when I was six. (able)
2. Are you able to understand sign language? (can)
3. If you start saving your pocket money, you'll manage to buy an MP3 player in six months. (able)
4. They weren't able to communicate because his speech wasn't clear. (couldn't)
5. It's impossible for me to sleep unless there's a light on. (can't)