根据对话内容，填上适当的句子，使对话句子完整
A：Hi，Bill！____.
B：Yes.I've already finished my homework.
A：____.
B：I'd like to work outside.
A：Me，too！____.
B：I'd like to do something to help others.Would you like to go with me?
A：Sure！Let's come up with a plan.____.In the afternoon we can visit the children's hospital to cheer up the sick children.What do you think?
B：____. But we had better join the school weekend volunteer program.
A：Good idea！We could do better then.
