нужно найти ошибки и исправить

6.Could you tell me why you look so upset?
7. I was sorry that I couldn't meet her after classes.
8. I don't know why they had not kept their promise to
take us with them.
9. Why didn't you say that we must translate the whole
article?
10. We were told that our parents will be coming back on
Saturday.
11. He asked me how I felt about going to school.
12. He said he thought it is rather silly idea and he was not
going to take part in it.
13. Do you know if Jane has received a letter from her
American pen-pal?
14. Didn't you know that they had been left for London?
15. He asked me whether I would go back there next year.
16. They asked him who he wants.
17. He said penguins can swim.
18. He asked her which hotel she was going to stay at.
19. Can you tell me is there a cafe near here?
20. I had no idea whose book that was.