We say "Time flies."
It does a lot of things, time does.
But only birds fly.
[And some squirrels, and even fish. Kites.]
It's interesting that we say "Time flies" as a sort of catch-all phrase meant to describe some inexplicable phenomenon -- and yet we also say, "Time stands still." Completely opposite expressions.
Denoting the fact that time is perhaps the greatest mystery of civilized mankind.
I say "civilized" mankind, because I think the concept of time is the very thing that civilizes [civilized?] mankind.
The contemplation of the brevity of what is.
There was a time when I thought of the New Century with a sort of awe.
Back in the 1980's - '90's -- I felt that the year 2000 was some sort of Ushering In Of The Future. All of a sudden everyone would look like aliens or something.
But look. The whole thing is close to a decade old!
We've made great advances in technology. And terrorism. And terabytes.
But [breathe in -- breathe out] -- nothing has flown.
Nor has anything stood still.
If anything, stuff has moved.