I. Read the dialogue.Then answer the question below!
Sam : What are you doing,Tommy?
Tommy: I’m fixing the wheels on my skateboard.
Sam : Do you need some help?I fixed the wheels on my skateboard yesterday.
Tommy : Thanks,but I can do it myself.
Sam : Do you know how to do it?
Tommy : Well,this is my first time.
Sam : Will you be careful?You might hurt yourself.
Tommy : Don’t worry.I’m sure I can do it.
What is Tommy doing?