"He is sad."
Translation:Han er ked af det.
There is "Undskyld" if you simply want to excuse for something (also used like engl "Pardon" eg. if you ask or interrupt someone). "Jeg er ked af det" is pretty much "I feel badly because of this", whether the situation is your fault or not. The "ked" is the same as in "Jeg keder mig" which means "I am bored" or in "kedelig" (boring, unfortunate, unpleasant, uncomfortable). So it's sort of expressing that you feel something that in a more or less unspecific way doesn't feel good ;)