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Sempai-kohai means seniority rules in Japanese relations. It seems every
culture has more or less respect for the eldery, but in Japan this is
especially strong. Sempai means elderly or those who are more able, and
kohai means a younger, or student. It is crucial to understand the
difference of these.
When talking to their superiors, Japanese use honorific keigo language.
There are various types of keigo, such as sonkeigo, teineigo and kenjogo.
Songeigo means that the speaker will raise the addressee by honouring him
with adding -sama - sensei to their names or titles. Samurai-sama.
Watanaba-sama. Kenjogo instead is style of speech what lowers the status of
the speaker himself, expressing humility. Teineigo instead is something
neutral between these.
Hanami Web - Inside Japan