Answer:
I can run but not walk. Wherever I go, thought follows close behind. What am I?
I am longer than a decade and shorter than a millennium
The more you take away from it the larger it becomes. What is it?
I have a name that's not mine and no one cares about me in their prime. People cry at my sight and lie by me all day and night.
I am the thing that is used to make your weight. What am I?
Dry though I may be, I am still a sea.