You can wear a gray shirt with brown pants, but you might want a real light gray or try a green shirt with brown pants might be better.
Yes.
brown work shoes
Gray.
Adebayor wear the number 25 shirt.
Yes if you want to. No if you don't.
Black, white, gray, or dark green.
yes
no but if you really want to wear those brown pants wear a yellow shirt.
Yes because the gray and the brown are neutral colors; therefore, the blue pants would look fine with the gray shirt and the brown shoes.
You can put on a red or black tie, but since gray is a neutral color, you can actually mix it with any color!
There are a number of Franciscan Orders which wear gray habits.