Solve the riddle:
Sometimes I shine, sometimes I’m dull, sometimes I am big, and sometimes I am small. I can be pointy, I can be curved, and don’t ask me questions because even though I’m sharp, I’m not smart enough to answer you.
What am I?

Below you will find a hint and the correct answer to the riddle.
Little hint:
Show Hint
Hint: Kn*f*.
Right answer:
Show answer
Answer: A knife.