"우리는 남자아이를 속입니다."
Translation:We deceive the boy.
I'm sure everyone in your circle knows what the word "deceive" means. Why, because they've all used it, read it, heard it on TV, etc. It even comes up in idioms, "appearances can be deceiving". According to Google, deceive comes up about half as often as the word "trick". It's not exactly an archaic word.