Answer:
I am the same written forward backward and upside down.
I am the book one can never finish reading
No matter how little or how much you use me, you change me every month.
I have more shoes than anybody but less feet than everyone. I am met in the morning but departed in the night. I may shake as if I'm angry but I won't bite.
Tuesday, Sam and Peter went to a restaurant. After eating lunch, they paid the bill. Sam and Peter did not pay. Who did?