(하)느라고 = Because i was busy doing something
This Korean grammar point is used when you are unable to do something because you were either interrupted or because you had been do something else.
Basically, the statement given in the preceding clause is the reason for, or cause of the following clause. Also note that this grammar point is a little negative in nature, and usually shorted to -느라.
학교하고 씨름 좀 하느라고…..(늦었어요)
I was dealing with school problems….(that’s why i am late)
Example of intermediate Korean grammar ~느라고
1. 주말에 뭐하셨어요? Over the weekend what did you do?
김장했어요. 김장을 하느라고 정말 힘들었어요. I make kimchi, that is why i am so tired(exhausted)
2. 뭐 좀 하느라고 늦었어, 미안… I was late because i was busy doing something,sorry…
3 저녁을 너무 맛있게 먹느라고 친구가 부르는 것도 몰랐어요. I could not hear my friend call me whilst i was eating dinner, because it was so delicious.