An arrow? A robbery?
Your Age.
Sun
What goes up when rain comes down is an umbrella.
your age
I think its an escalater The Answer to the first part of this question is Age, and hot air. The 2nd part would be anything ground-based as well as an escalator.
Something that reaches the escape velocity of the body its coming up from.
a traveller on a donkey.
What goes up when rain comes down is an umbrella.
a stair case
The years never go down addition your age and the time
Vomit
age
age
your age
your age
rain
your age
A waterfall
Age.