Riddle: I'm under your face, I'm outside your mind; A biological case, Pressure brings pain sometimes. What am I?
Answer: Your skull.
Riddle: We both come together, But one comes first. What am I?
Answer: Twins.
Riddle: I'm clean when I'm black, Dirty when white; Get too close, And you might sneeze. What am I?
Answer: A Chalkboard.
Riddle: You have me today, Tomorrow you'll have more; As your time passes, I'm not easy to store; I don't take up space, But I'm only in one place; I am what you saw, But not what you see. What am I?
Answer: Memories.
Riddle: I'm essential to most flight, But can't fly on my own. What am I?
Answer: Feathers.
Riddle: Very few men have ever been here, But one man has been for thousands of years. What am I?
Answer: The moon.
Riddle: I'm rough to the touch; Blood does me through veins; I can be taken in math; The path of a plane. What am I?
Answer: Coarse/Course
Riddle: You can't see me, but I can see you; To be more specific, I see through. What am I?
Answer: An X-Ray.
Riddle: I like to roam but I'll always stay home, I leave a silver track, If you carried what I could carry with the way I moved, You'd break your neck and back. What am I?
Answer: A Snail.
Riddle: I can be thin, but not fat; You need me around, I promise not to crowd you; Some use a lot of me, especially if they like to chat. What am I?
Answer: Air.