从所给出的单词中选出合适的完成对话。
What's Let's can't first pupil
Pat:____the matter?
Tim: I am sad today. I____ run fast. I'm not a good____.
Pat: That's not true.
Jane: Come on, Tim.____ run.
Pat: Go and try, Tim.
Jane: Wow! Look at Tim! He is fast!
Tim: I'm ____! I can run fast.