(으)러 is a non-final ending for action verbs. It is used to convey the purpose of an action. It is used in conjunction with movement verbs and shows the purpose of that ‘movement.’ These movement verbs are typically in the form of either 오다 (oda) – to come, or 가다 (gada) – to go, and their variations.
This structure can be translated as ‘in order to.’
-러 is used for verb stems ending in vowels.
-으러 is used for verb stems ending in consonants (except verb stems which end with the consonantㄹ)
1.사다 (sada) – to buy – the verb of purpose [Verb1]
가다 (gada) – to go – movement verb [Verb2]
Verb1 stem + 러 + Verb 2
사 + 러 + 가다
2.먹다 (meokda) – to eat – the verb of purpose [Verb1]
오다 (oda) – to come – movement verb [Verb2]
Verb1 stem + 으러 + Verb 2
먹 + 으러 + 오다
Tense, and/or negation are inflected in Verb2, the movement verb.
(I)’ll go (in order) to meet (him.)
2.공부 하러 왔어요.
(gongbu hareo wasseoyo.)
(I) came (in order) to study.
3.점심 먹으러 왔어요.
(jeomsim meokeureo wasseoyo.)
We came (in order) to eat.
4.책 사러 학교 간다고 했어.
(chaek sareo hakgyo gandago haesseo.)
He said he was going to school (in order) to buy a book.