Complete the task

Find and correct four mistakes in the sentences below. If there's no mistake, press Enter (↲).

1. I [ ] to Patrick's party. I'm sick.
2. They [ ] us in the summer, aren't they?
3. Trust me, I [ ] you down!
4. I think I
   [ ] the concert this time.
5. I can't watch the game with you. I [ ] on a date with my girlfriend.
6. A: Would you like a salad?
   B: No, thanks, [ ] have a sandwich.
7. [ ] enter a university?