"Friends are good."
This is a general statement about friends. Also the verb 좋다 can mean "to like" if a topic is specified or implicitly a person. E.g. (나는) 사과가 좋습니다 reads "With respect to me, apples are good" which basically means "I like apples". Note how 사과가 좋다 differs from 사과를 좋아하다 ("apples are good" vs "to like apples")