'nega(네가)' is you. n 'naega(내가)' is i. i think maybe u talk 'naega' I speak to Korean '나(na),내(nae),저(jeo),제(je)' You speak to Korean '너(neo),네(ne),당신(dangsin)' people scarcely say "네가(you)" to other one, but use much when writing. "저","제" r low(humble) talk. "당신" is honorific talk. it is used in this situation when people say to 1st meet or unfamiliar or older man etc.