Best riddles

My life can be measured in hours. I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.

This guy living on the 20th floor in an apartment building got up early each morning to go to work in a downtown store. He always went into the elevator on the 20th floor and rode down to the entrance (1st floor). When he came home he always rode the elevator from the entrance and up to the 8th floor. He walked out of the elevator and walked the stairs up to his apartment on the 20th floor. Why didn't he take the elevator all the way up to his apartment?

I'm in your phone. Sometimes I laugh. Sometimes I cry. I even flip you off from time to time. What am I ?

What is the similarity between your eyes and your school?

This very thing you were born with pleases us all. It's even capable of making men fall, while only experienced by few it's treasured by all.

2+3=8, 3+7=27, 4+5=32, 5+8=60, 6+7=72, 7+8=? Solve it?

You will throw me away when you want to use me. You will take me in when you don’t want to use me. What am I?

What did the boy bird say to the girl bird on Valentine's Day?

What is the difference between yesterday and tomorrow?

How far can you run into the woods?