Answer:
I'm tall in the morning and short in the noon. I disappear at night but I will be back soon.
I'm light as a feather, yet the strongest man can't hold me for more than 5 minutes.
Sharp and long, flag of the world. What is it?
They're up near the sky, on something very tall. Sometimes they die, only then do they fall.
I count time, but have no end. Tick tick, but I am not a clock. What am I?
When is it bad luck to see a black cat?