What's the difference between 네가, 니가, 내가? and how do I use 은, 는? So difficult Question !! But I try my best to write you ! First of all ! 네가 and 니가 have same meaning !! It means "You are" "네가" is correct way.However most of Koreans use "니가" because it sounds more easy ^^ we don't distinguish here 내가 means "I am" 은,는 is a 보조사(補助詞]) I can't find the English word for it. I think it is "assistance word" X) You use it after the subject .

은,는 are called topic particles that are are used and placed after the subject to give emphasis on the subject. :) Use 은 if the subject ends in a consonant. Use 는 if the subject ends in a vowel.. e.g. Naneun (나는) There are also other particles.... ^o^