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Beginner 2 > Lesson 17

Lesson 17. How to say “so, therefore” 그래서, V/A-아/어서 & “because~” V/A-기 때문이다, Noun 때문이다 

그래서 (sentence connector) : therefore
V/A + 그래서 = V/A-아/어서 (conjunction)


1. Verb/Adj + /(Present stem) +

Ex. 아프다 (to be sick) = 아파서(요)

저는 아파서 병원에 가요 = I am going to the hospital because I am sick.

저는 어제 아파서 학교에 안 갔어요 = I didn’t go to school yesterday because I was sick.*

*This form can be used to refer to both, Present or Past tenses.

So, 아파서요 can mean either: 1) Because I am sick or 2) Because I was sick.

Hence, it would be INCORRECT to use past stem while attaching -서 to it, and only Present stem should be used, even if it means past tense.

Ex. 공부하다 (to study) = 공부해서

  • 왜 성적이 좋아요? = Why are your grades good?
  • 공부를 열심히 해서요 = Because I studied/study hard.

Ex. 먹다 (to eat) = 먹어서

너무 많이 먹어서 배가 아파요 = My stomach hurts because I ate a lot.

Ex. 몸이 안 좋다 (to not feel good) = 몸이 안 좋아서

몸이 안 좋아서 밖에 못 갔어요 = I couldn’t go out because I wasn’t feeling good.


Using –이다 verb (to be) with –:

When using -이다 verb with -서, it follows a slightly different rule: Noun+이어서/여서.

If the Noun has a 받침, use Noun+이어서 and if it doesn’t have a 받침, use Noun+여서.

Ex. 오늘 내 생일이어서 = Because it is my birthday.

Ex. 저는 여자여서요 = Because I am a woman.

In the same way, Noun+이라서/라서 can also be used.

If the Noun has a 받침, use Noun+이라서 and if it doesn’t have a 받침, use Noun+라서.

Ex. 오늘 내 생일이라서 = Because it is my birthday.

Ex. 저는 여자라서요 = Because I am a woman.

It is possible to omit 서 in this form.

Ex. 내일이 시험이라(서) 공부해요 = I am studying because there is an exam tomorrow.

Ex. 주말이라 수업이 없어요 = Because it is the weekend, there is no class.


+) Additional Grammar Point (not covered in the video)

It is also possible to combine the FUTURE TENSE stem with 아/어서, in which case it would be :
Verb-ㄹ/을 거라서” or “Verb-ㄹ/을 거여서


저는 내일 학교에 안 갈 거라서 (=갈 거여서) 늦게 자도 괜찮아요. = I’m not going to school tomorrow, so it’s okay to sleep late.

이따가 저녁을 많이 먹을 거라서 (=먹을 거여서) 점심을 조금 먹었어요. = I will be having a lot of dinner later, so I had small lunch.


2. V/A-기 때문이다

FOR PRESENT TENSE: V/A(Base stem) + 때문이야/때문이에요.

FOR PAST TENSE: V/A-았/었(Past Stem) +기 때문이야/때문이에요.

Ex. 아프다 (to be sick) = 아프기 때문이에요.

  • 왜 병원에 가요? = Why are you going to the hospital?
  • 아프기 때문이에요 = Because I am sick.
  • 아팠기 때문이에요 = Because I was sick.

Ex. 공부하다 (to study) = 공부해서

  • 너는 왜 성적이 좋아요? = Why are your grades good?
  • 공부를 열심히 하기 때문이야 = Because I study hard.
  • 왜냐하면* 공부를 열심히 했기 때문이야 = Because I studied hard.
    *You can also start the sentence that ends in -기 때문이야 with 왜냐하면. It is kind of like saying, “to tell you the reason why~.”

Using – 때문이야 with Nouns:

  1. Noun+때문이야/때문이에요 = It is because of (Noun)

Ex. 너 때문이야! = It is because of you!

Ex. 엄마 때문이에요 = It’s because of mom.

  1. Noun+때문에 + Subject + Verb = It is because of (Noun) + resulting sentence.

Ex. 날씨 때문에 안 갔어 = I didn’t go because of the weather.

Ex. 친구 때문에 늦었어요 = I got late because of my friend.