Ответ:
1. I can cook, but not as well as my mother.
2. I can't finish my book by the end of this week? I'm sorry.
3. My nephew can play chess very well - he has won several competitions.
4. I can't speak Polish now, but I might be able to learn a little bit next year.
5. My grandparents can use the computer. They have never learnt.
6. Oh no, it's raining! We can't have a barbecue tonight.
7. We can't afford to go on holiday this year. We don't have enough money.
8. Jason can't take care of me now, but he might be able to take care of me when I'm 90.
9. They can fix the TV today, but they can't do it tomorrow.