-고말고요
→ It indicates the affirmation and accentuation of a preceding part by adding to a stem of a verb or an adjective. That means agreeing strongly with the other party's opinion, questioning or accepting willingly the other party's order, request, or demand.
Example:
가: 문경호 씨가 일을 잘하나요? Does Mr. Mun Gyeongho work well?
나: 잘하고 말고요. 신입 사원 같지 않아요. Yes, he does. He doesn't seem to be new.
가: 승우는 똑똑하니까 이 정도 책은 어렵지 않겠지요?
As Seungwoo is smart, isn't this book too hard for him?
나: 어렵지 않고 말고요. Absolutely not.
가: 내일 저를 좀 도와주실 수 있어요? Can you help me tomorrow?
나: 네, 도와드리고 말고요. Of course, I can.
가: 우산을 안 가져 왔는데 우산 좀 빌릴 수 있을까요?
I didn't bring an umbrella. Can I borrow it?
I didn't bring an umbrella. Can I borrow it?
나: 우산을 빌려 드리고말고요.
Don't lend me an umbrella.