For example when greeting.
Englishman asks me: How are you?
I answer: I`m fine. Thanks
If a russian asks me "Как дела?"
I will answer: "Хорошо. Спасибо"
In this case "Хорошо" is equal to "I`m fine". Also "хорошо" is russian equivalent of "good", "well", "OK" and is used in the same cases, in which all the words are used in English.
Unfortunately I don`t know Korean :-(