너 (neo) – 'You' – Singular – Generally, this second-person pronoun is used by a speaker who holds a great deal of power in the relationship, or when both speakers share an equal amount of power in the relationship. This word is used when the speaker does not feel the need to respect the listener. (i.e. extremely close friends, older people talking to younger people, people of high positions)
Note: A boss would not use this word because respect would be necessary in an office atmosphere (even with the difference in social hierarchy).
너희 (neohui) – 'You' – Plural – This would be used in situations when a speaker is addressing a group and when he or she holds the power in the relationship. Just like the singular 너 (neo), it would be used when the speaker does not feel the need to respect the other party. In most cases it is used towards children.
Note: 너희 (neohui) is often followed by the pluralizing suffix 들 (deul).
당신 (dangsin) – 'You' – Singular – A second-person pronoun that is often used for (1) neutrality and distance (2) a term of endearment between a couple (typically married) (3) speaking in a condescending or confrontational manner.
Note: 당신 (dangsin) is politer than 너 (neo), but is still not considered very polite because it is too direct to refer to someone as 'you' unless the two parties are on familiar terms. Therefore it is often used to confront strangers, or those that have no prior relationship.
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