根据对话内容，在空白处写出恰当的句子，是对话意思连贯完整。所写句子应与所给的标点符号一致。（共5个句子，每句1分，满分5分）
A: Hey, Steve! Over here! 小题1:_________________?
B: Oh, wow! You’re Paula, aren’t you?
A: 小题2:___________________________.
B: But you used to be really quiet, 小题3:_________________ ？
A: Yeah. I wasn’t very outgoing.
B: No, you weren’t. But you are always friendly. Wait a minute! Did you use to play the piano?
A: 小题4:_________________.But now I am more interested in sports. I play soccer and go swimming every day.
B: Wow! 小题5:________________________________.
，则f’（x）=()．
