Answer:
My second is performed by my first, and it is thought a thief by the marks of my whole might be caught.
If you drop me I'm sure to crack. But give me a smile and I'll always smile back.
Man's most important invention.
What age most travelers have?
Watches students at the prom to make sure there's no funny business.
I touch the Earth, I touch the sky, but if I touch you, you’ll likely die. What am I?