Let's Learn Korean - Particle 어서/아서 -

요즘 내 제일 좋아하는 노래라서 꼭 들려 주고싶어는데..

This particle is the conjunction of clauses in sentence. It shows causal relationship between actions or conditions. The meaning of it is 'so', 'because', 'and then' and 'after that'. 아서 is for root word which ends by 오 or 아, while 어서 is for root word which ends by another vowels and consonants.


Example:  -   그 사람을 너무 화나서 제가 안 만나고 싶어요  =  Because I'm so angry with him, i don't wanna meet him 

                  -  나는 자서 엄마를 도움지 않았어요  =  Because i was sleeping, i didn't help mum

                  -  어제 셰릴 같이 놀어서 숙제를 했어요  =  Yesterday i played with Cheryl then did my homework

                  

There are any 2 restrictions of using this particle. 1st, the tense doesn't change. Now take a look to the 2nd example. 자 doesn't change into 잤어. The tense is only showed in the predicate of the second clause, 않았어요. 2nd, when this particle is used to declare the causal relationship, it can't be used for command and suggestion sentence.

Example:  -  우리는 시간이 있어서 동물원에 갑시다!  = Let's go to the zoo since we have the time!

                  -  시간이 있어서 동물원에 가요  =  I go to the zoo since i have the time

The 1st example is incorrect because it doesn't obey the 2nd rule of using this particle. But the second example is correct because it's not a suggestion nor command sentence.

The combination between 어서/아서 and copulas will make different form. With 이다, the positive copula is (이)라서/이어서 and the negative is 아니라서/아니어서. (이)라서 and 아니라서 are commonly used by people.

Example:  -  저는 동방신기의 팬이라서  =  Because I'm a fan of TVXQ!

                  -  저는 동방신기의 팬이어서  =  Because I'm a fan of TVXQ!

                  -  저는 동방신기의 팬이 아니라서  =  Because I'm not a fan of TVXQ!

                  -  저는 동방신기의 팬이 아니어서  =  Because I'm not a fan of TVXQ!