Answer:
This is needed both for courage and hardcover books.
In many years, not much has happened. In many minutes, a lot has happened. In one second, everything has happened.
What has a big mouth, yet never speaks?
What begins and has no end? What is the ending of all that begins?
What runs around all day. Then lies under the bed. With its tongue hanging out?
People take me on walks and I run and have fun. What am I?