'뭐해요?' vs '뭐하세요?'
I encountered these expressions today. It seems that both are used for asking the question, "What are you doing?". I would like to know when I should use one and not the other? Thank you in advance...

Question

Answer

안녕하세요!

This lesson will explain the difference :)

Level 5 Lesson 2 / -시- (honorific) / -시-, 하시다
http://www.talktomeinkorean.com/lessons/level-5-lesson-2/

감사합니다

Answer

해요 is propositive present informal high
하세요 is imperative present informal high

so these are similar but '뭐해요?' is more for intimate person than '뭐하세요?'.
I would not  say '뭐해요?' to my teacher, stranger, elder(who is not familiar)

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