A Japanese question?

[Eurasian]

"san" is kind of like "mr/mrs/ms."

"chan" is even friendlier than "san." it's used for little kids and girls. when u use "chan," u gotta know this person. and u usually use the first name then add "chan" after it.

"kun" can be used on male classmates. but u can use it w/ colleagues. i think that parents also say it when they discipline the kids.

"senpai" is used for superiors. like in school, u use it on students who r in higher grades than u. but i think u can use it on ur colleagues who have been there longer.

[Assassin]

^ what she said