Answer:
I can swim but never get wet. I can run but never get tired. I follow you everywhere but never say a word.
I am a protector. I sit on a bridge. One person can see right through me while others wonder what I hide.
What force and strength cannot get through I with my unique teeth can do.
I always go to bed with my shoes on.
What gets bigger the more you take away?
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.
What am I?
Animal
Difficult
Easy
Food
Funny
Kids
Logic