Предложения поставить в отрицательную форму. 
1.Toyoto cats are made in Germany.
2.John Lennon was singing on stage when he was killed.
3.We`ve been in class for eight hours.
4.Gagarin flew to space in 1969.
5.We`ve sitting at home.
6.We`ve been studying English for twelve years.
7.The sun rises in the west.
8.Rice is grown in Britain. 

1.Toyoto cats aren't made in Germany.2.John Lennon wasn't singing on stage when he was killed.3.We haven't been in class for eight hours.4.Gagarin didn't fly to space in 1969.5.We haven't been sitting at home. (проверь, так написано?)6.We haven't been studying English for twelve years.7.The sun doesn't rise in the west.8.Rice isn't grown in Britain.

1. Toyoto cats aren't made in Germany.2. John Lennon wasn't singing on stage when he was killed.3. We haven't been in class for eight hours.4. Gagarin didn't fly to space in 1969.5. We haven't been (???) sitting at home. 6. We haven't been studying English for twelve years.7. The sun doesn't rise in the west.8. Rice isn't grown in Britain.