根据对话内容，在横线处填入正确的单词，使对话完整。

A: What are you doing, Bill?

B: We are raising money for "Helping Future Project".

A: I have __1__ heard about it before. What is it about?

B: It is aimed to help poor and homeless kids in different parts of the world.

A: What a great charity! I also want to __2__ some money.

B: Really? All poor and homeless kids will be thankful to you for your __3__.

A: But I'm __4__ I can't donate too much. You know, I'm just a student and I don't have much money. I

    can only donate 200 yuan.

B: That's __5__. A sincere heart is the most important. Thank you very much.