"The man puts out the fire."
Translation:남자가 불을 끈다.
화재 is a Sino-Korean word whereas 불 is a pure Korean word.
화재 is a proper incident involving or caused by fire regardless of size but 불 is just fire.
The firefighter puts out the fire in a training. = 소방수가 훈련에서 불을 끄다
훈련 =drill = training
산불 = forest fire
화재 = 화마 (This is somewhat poetic expression yet newspapers often use this word rather than 화재 to make the headline more dramatic, eye-catching.)