Find and correct the mistakes. Three of the sentences are correct.

1. After we had been on a school trip together, we had become close friends.

2. As soon as they had made up with each other, they fell out again!

3. We had an argument because he had criticised my work.

4. By the end of the first week, she had made friends with all her classmates.

5. When they had beaten the other team, they had gone back to their secondary school.