Answer:
What occurs once in a minute, twice in a moment and never in one thousand years?
What has been around for millions of years but is never more than a month old?
What can you hold in your left hand but not in your right hand?
I am the first you ever saw, what greets you every morning and what goes out in the end.
The thinkers usually hold this body part
People take me on walks and I run and have fun. What am I?