МОДАЛЬНЫЕ ГЛАГОЛЫ! Перейдя по ссылке, изучите самостоятельно модальные глаголы и выполните несколько заданий:
http://ok-english.ru/spisok-modalnyih-glagolov-i-konstruktsiy-angliyskogo-yazyika/

1. Last week we  swimming, this week we can't. (can/to go)
2. Maybe the Smiths  a new house next year. (can/to build)
3. If you try hard, you  your examinations. (can/to pass)
4. When I was five, I . (not/can/to swim)
5. Dennis  the trumpet after four months. (can/to play)
6. Luke has passed his driving test, now he  a car. (can/to drive)
7. I  to him on the phone for three weeks last month. (not/can/to speak)
8. Alex  his homework when his desk is in such a mess. (not/can/to do)
9. They were so busy, they  me. (not/can/to text)
10. Lisa  her dress. She can wear it again. (can/to clean)