Gryffindor: What does 멍청이(mung chung ii) mean?

Ravenclaw: Stupid.

Hufflepuff: Ravenclaw, that's mean.

Gryffindor: Yeah! Not everyone is as smart as you!

Ravenclaw: It means stupid.

Gryffindor, Hufflepuff: Oh.

Slytherin: Stupid.

Gryffindor, Hufflepuff: 

Ravenclaw: Oh, it's not like you knew.

Slytherin: