Let’s say that you see a painting and you say ‘그 여자는 누구예요’? (그 = that. 여자 = girl. 는 = topic marking particle. 누구 = who. 예요 = copula meaning ‘is’.) In English this sentence would mean, ‘Who is that girl?’ As a response the artist of the painting could reply, ‘여가가 아니에요’ or ‘it’s not a girl’. Take a look at another example, 저는 한국 사람이 아니에요, (저 = I. 는 = topic marking particle. 한국 = Korean. 사람 = person. 이 = subject marking particle. 아니 = not. 에요 = means ‘am’.) which means ‘I am not a Korean person’. In this case, 아니에요 takes on the meaning of ‘am not’.

The word 아니에요 negates things. In the sentence above 아니에요 takes on the meaning of ‘not’. However 아니예요 can also take on the meaning of ‘no’. For instance in this sentence, 아니에요, 저는 미국 사람이에요, the 아니에요 takes on the meaning ‘no’ instead of ‘not’. (아니에요 = no, in the standard polite form. 저 = I. 는 = topic marking particle. 미국 = America. 사람 = person. 이 = subject marking particle. 이에요 = is.) In English the sentence means, ‘No, I am not an American person’. You can also say, 아니에요, 저는 한국 사람이 아니에요. 저는 미국 사람이에요, which emphasizes that you’re not a Korean person even more.

Generally when 아니에요 is placed at the beginning of the sentence, it takes on the meaning of ‘no’. When 아니에요 comes at the end of the sentence, it takes on the meaning of ‘not’. Also, the meaning ‘no’ and ‘not’ can also be expressed as 아닙니다. 아니에요 is the standard polite way of saying ‘no’ or ‘not’, but 아닙니다 is the deferential polite way of saying ‘no’ or ‘not’. For example you could say ‘저는 아닙니다’ or ‘it’s not me’. (저 = polite way to say ‘I’. 는 = topic marking particle after a vowel. 아닙니다 = deferential polite way of saying ‘not’.)

You can also use 아니에요 and 아닙니다 in the interrogative form. For example you could say, 승미 집이 아니에요? or 주나 씨 아닙니까? In English this would mean something like ‘It’s not Sungmi’s house?’ or ‘Are [you] not Mr. Juna?’ (승미 = Sungmi (a person’s name). 지 = house/home. 이 = subject marking particle used after consonants. 아니에요 = ‘not’. 주나 = Juna. 씨 = can mean Mr./Ms. 아닙니까 = deferential interrogative form of ‘not’.) You might have also noticed that 아니에요 is not spelled as 아니예요, the difference being that one has the 에 and the other has 예 even though 아니 ends in a vowel. That’s because 아니 is not a noun, and so it doesn’t follow the normal conventions for vowel and consonant endings.