Combining Rules

We combine multiple sentences to communicate our meaning clearly.

For example, we combine sentences like these:

I told her.
She was buying a cup of coffee.


I told her who was buying a cup of coffee.

We combined 2 short sentences into a long sentence by using a relative pronoun. We’ll learn how to do similar thing in Korean from today.

Before we do that, I want to tell you about some rules.

Don’t use 그리고, 그러나 in the middle of sentences

First of all, unlike English, you cannot use connecting words like 그리고, 그러나 when combining sentences. For example, when you’re listing 2 facts, you can use “and”.

I ate pizza and drank Coke.
I ate pizza. And I drank Coke. (Yes, I know that grammar teachers will be mad at you if you use sentences like this. But we all know that it’s really common in modern English.)

But you cannot use 그리고 in the second case.

나는 피자를 먹었다. 그리고 콜라를 마셨다. (o)
나는 피자를 먹었다 그리고 콜라를 마셨다. (x)
-> 나는 피자를 먹었고 콜라를 마셨다.

You need to learn 2 words: 그리고 and -고.

Tense rule is different

Second, the tense rule is a bit different. In English, you should use the same tenses that happened in the past, but in Korean, you should avoid it sometimes. It’s different from ending to ending.

열심히 공부했지만 합격하지 못했다. (o)
열심히 공부하지만 합격하지 못했다. (x)
I studied hard but I couldn’t pass it.

아저씨가 오셔서 컴퓨터를 고쳐 주셨다. (o)
아저씨가 오셨어서 컴퓨터를 고쳐 주셨다. (x)
He came and repaired the computer.

나는 피자를 먹었고 엄마는 스파게티를 드셨다. (o)
나는 피자를 먹고 엄마는 스파게티를 드셨다. (o)
I ate pizza and mom ate spaghetti.

As you can see, you cannot use present tense with “-지만”, but you must use it with “-서”. Interestingly, it doesn’t matter what you use with “-고”.

Subjects and endings

Third, a subject is required for some endings.

서울대에 합격했다고 이야기하자 모두들 기뻐했다.
When I told them I entered Seoul National University, everyone loved it.

In this sentence, you cannot remove 모두들.

나는 피자를 먹으면서 친구들은 이야기를 했다. (x)
우리는 피자를 마시면서 이야기를 했다.
We’re having a chat while eating pizza.

Some endings and types of words

Fourth, sometimes you cannot use some endings with some types of words.

기분이 좋으려고 노력해 보세요. (x)
기분이 좋아지기 위해 노력해 보세요. (o)
Try to feel good about yourself.

훌륭한 유튜버이려고 공부를 많이 했어요. (x)
훌륭한 유튜버가 되고 싶어서 공부를 많이 했어요. (o)
I studied a lot to be a great YouTuber.

You cannot use 이다 and adjectives with “-(으)려고”.

Some endings and types of sentences

Fifth, in some cases, you cannot use some types of sentences with some endings.

추워서 창문을 닫자. (x)
추우니까 창문을 닫자. (o)
It’s cold. Let’s close the window.

추워서 창문 닫아. (x)
추우니까 창문 닫아. (o)
It’s cold. Close the window.

You cannot use “-서” in commanding or requesting sentences.

Some endings and negative sentences

Sixth, some endings don’t work with negative sentences.

만화를 보지 않느라고 책을 펼쳤다. (x)
만화를 보지 않으려고 책을 펼쳤다. (o)
Not to watch an anime, I opened a book.

You cannot use “-느라고” with negative sentences.

There are more examples of these. We’ll see them in detail when we cover each ending.