我觉得我以前回答过这个问题。^^ I think I've replied for this question before in here. They all refer to "I" , and used in a different way depending on the relationship between listeners and speakers or the situation where you are in as well. 对长辈或者上级我们用"저(我)"还有 对小辈或者朋友之间,同辈....用"나(我)" "나(na)" is used in informal contexts, and when a speaker doesn't need to show respect to a listener like a friend or a person who is younger than the speaker while "저(jeo) is a polite version of "나" and used in a sense of respect to others. "내"是“我的”的意思。 比如说“这是我的手机” 이것은 내(=나의) 핸드폰 입니다. "내" means "MY" , and it's a contraction of "나의". For example, This is my mobile phone 이것은 내(=나의) 핸드폰 입니다. 나,저 变成 "내","제" 和主格词尾"가"，属格词尾 "의" 连用时。 When used in conjugation with the subject marker "가"or the possessive particle "의", "나","저" change to "내","제". 나+의 = 내(对小辈-"我的" to friends or younger persons than the speaker meaning "MY") 저+의 = 제(对长辈-"我的" to older persons or superiors, and also means "MY") 나+가 = 내가(对小辈- "我") 저+가 = 제가(对长辈- "我") 比如说， "我去." 对长辈应该说........"제가" 가겠습니다. 对小辈,同辈 ........."내가" 갈께. For example, "I will go" can be translated as.... 1."제가" 가겠습니다.(polite) or 2."내가" 갈께.(not polite) ^_____^

I've answered the same question before on Italki so I think I'm gonna copy and paste my previous answer because it's much explaining~ here you go~ You use naega 내가 when you are referring to yourself in the sentence, kind of like 'I am'. Nae 내 means 'I', it's used only with the topic marker ga 가. For example, if you say "I am going to the store." you would say Naega gagey ey ga 내가 가게에 가. Na 나 is used in a situation where the speaker is the subject or object of the sentence. It's always used with the subject marker nuun 는 (or object marker reul 를, I'll get to that). If I said, "I don't like football." I would say Na nuun 나는 (usually in colloquial it's contracted to 'Nan 난') chukguga shiro. 난 축구가 싫어. (Sometimes in colloquial Korean the subject '나' is left out of a sentence like this, as well as the topic marker 가 and you could just say 'Nan chukgu shiro or chukgu shiro.) Reul (를) is the object marker, so you would use Nareul 나를 as we use 'me' in a sentence . If you want to say, ''Yuna Kim loves me." you would say Kim Yunaga nareul saranghae 김연아가 나를 사랑해. Just want to explain more so you won't be misunderstood if you are talking to a Korean person ^^ because in Korea you have to be careful in your speech ;D it shows how mannered you are ^^ nae/na 내/나 are used in very informal speech (ban mal 반말). As a general rule, be careful when using ban mal and all forms of the word 'you' (ney,ni,no,dangshin 네,니,너,당신). It's only ok if you are talking to children, close friends of the same age or younger, family (but never older people) or your lover.

I've answered the same question before on Italki so I think I'm gonna copy and paste my previous answer because it's much explaining~ here you go~ You use naega 내가 when you are referring to yourself in the sentence, kind of like 'I am'. Nae 내 means 'I', it's used only with the topic marker ga 가. For example, if you say "I am going to the store." you would say Naega gagey ey ga 내가 가게에 가. Na 나 is used in a situation where the speaker is the subject or object of the sentence. It's always used with the subject marker nuun 는 (or object marker reul 를, I'll get to that). If I said, "I don't like football." I would say Na nuun 나는 (usually in colloquial it's contracted to 'Nan 난') chukguga shiro. 난 축구가 싫어. (Sometimes in colloquial Korean the subject '나' is left out of a sentence like this, as well as the topic marker 가 and you could just say 'Nan chukgu shiro or chukgu shiro.) Reul (를) is the object marker, so you would use Nareul 나를 as we use 'me' in a sentence . If you want to say, ''Yuna Kim loves me." you would say Kim Yunaga nareul saranghae 김연아가 나를 사랑해. Just want to explain more so you won't be misunderstood if you are talking to a Korean person ^^ because in Korea you have to be careful when you speak ;D nae/na 내/나 are used in very informal speech (ban mal 반말). As a general rule, be careful when using ban mal and all forms of the word 'you' (ney,ni,no,dangshin 네,니,너,당신). It's only ok if you are talking to children, close friends of the same age or younger, family (but never older people) or your lover.