Answer:
I'm not man's best friend, I'm their enemy, I can mark your end, yet you do not see me, I am very small, but very tough, If you have me, then you have it rough.
What moves without seeing and cries without eyes?
Which button does not function when being pressed?
I never was but always will be. No one ever saw me but everyone knows I exist. I give people the motivation to better themselves every day. What am I?
What liquid can contain the soul?
What did the piece of wood say when he saw the screwdriver and screws approaching?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?