NOUN + OR + NOUN
In order to link two nouns, you can use -(이)나.

After nouns that end with a consonant, add -이나.
After nouns that end with a vowel, add -나.

Examples:
공원이나 영화관 = a park or a movie theater
학생이나 선생님 = a student or a teacher
여기나 저기 = here or there

You can also use the word 아니면, which literally means “if not”.

Examples:
공원 아니면 영화관
학생 아니면 선생님
여기 아니면 저기

VERB + OR + VERB
Since adjectives are essentially “descriptive verbs” in Korean, adjectives and verbs are linked in the same manner. After verb stems, you can use -거나.

Examples:
먹거나 = eat or…
전화하거나 = make a phone call or…
집에 가거나 = go home or...

The tense (present, past or future) is expressed through the last verb, so the last verb has to be conjugated accordingly to show the tense of the entire sentence.

Examples:
집에 가거나 친구를 만날 거예요.
= I will (either) go home or meet a friend.

“가다” is changed to “가거나” but you don’t add “-거나” to “만나다”.
Sometimes people add -거나 to all of the sentences (Ex: 집에 가거나, 친구를 만나거나) and in that case, they use the verb 하다 (= to do) to finish the sentence.

Examples:
집에 가거나 친구를 만나거나 할 거예요.

In addition to using -거나 at the end of the sentence, you can add 아니면 as well between the two actions.

Examples:
집에 가거나 아니면 친구를 만날 거예요.
* There are other ways of saying “or” with verbs, such as “-든지” and “-든가” but more on those in future lessons!

SENTENCE + OR + SENTENCE
In previous usages, we’ve seen that -(이)나 is used with nouns and -거나 is used with verbs. When you want to say “or” between two sentences, you simply use 아니면. 아니면 can be broken down into “아니다 (= to be not) + -(으)면 (= if)”. 아니면 literally means “if not” or “if that’s not the case”.

Examples:
집에 갈 거예요? 아니면 친구를 만날 거예요?
= Are you going to go home? Or are you going to meet a friend?

이거 살 거예요? 아니면 다른 거 살 거예요?
= Are you going to buy this? Or are you going to buy something else?

You could say these sentences without “아니면”, but it sounds more natural including it between the two sentences.
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