Cindy, Jenny and Mary are talking about what a good friend should be like.
Cindy: I think a good friend should be honest (诚实的). That's more important than any other thing. And it is where a friendship starts. If a friend isn't honest, he may lose his friends' trust.
Jenny:I think a good friend has to be generous (慷慨的). Here being generous doesn't mean he has to give his friends his lunch money or his clothes. It means he should share his ideas and feelings with his friends. In fact, his friends can know him better in this way.
Mary: In my opinion, a good friend should understand his friends. When there's something wrong between him and his friends, he must put himself in his friends' place and think more about his friends.