Good Riddles

Question: When I left, I didn't know where I was going; when I got there, I didn't know where I was; when I returned, I didn't know where I had been. Who was I?

Question: What season is it when you are on a trampoline?

Question: 123-----111213-----31121113-----? What is the next term in the sequence?

Question: What's the difference between Ms. and Mrs.?

Question: Which book will never be written?