✔ 最佳答案
You know your question is hard for the answerer to put the answers into sentences.
There are descriptions and phrases describing unfavourable behaviours of friends.
eg.
1. insincere
2. lying
3. cheating
4. backstabbing
5. rude
6. taking revenge
7. spreading rumours
8. talking behind a friend's back
9. teasing
10. looking down upon a friend
I hope this helps~