火 -- a man on FIRE!
火 pronounced 화
"hwa", as in "hwaah, I'm burning!"
화요일 -- Tuesday
화산 -- volcano (lit. fire mountain)
화나다 -- to be angry
방화하다 -- to set fire to
火 pronounced 불
"bull", an angry animal that doesn't like red rags
불금 -- Burning Friday (lit. Fire Friday), or TGIF
불을 켜다/끄다 -- to turn on/off a light