When do you use formal language in Korean? In which occasion do I have to use formal language? When do I use the most formal language, when the normal language and to who can i use informal language? How do I adress a stranger (e.g. asking for directions, taxi diriver, shop assistant, waiter) ? Which form do I use if I am not sure whether the person is older or younger? What do I use in the internet? Do the same rules apply? just a basic rule, if there are important exceptions, can you mention them as well? Sorry for the long question, I am just curious :)