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 is yellow, looks like the moon and has seeds?
Runs smoother than any rhyme, loves to fall but cannot climb!
What runs around all day. Then lies under the bed. With its tongue hanging out?
The itsy bitsy teeny weeny yellow polka dot variety is quite popular.
What language does a billboard speak?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?