"너희" means "you, you guys, both of you" In Korean, There is an honorific. So you need to use the honorific to older people llike your teacher, father, mother, someome who you respect for. When you call "너희" to someone. This someone is yonger than you like your brother, sister, junior colleague, younger studuents.... e.g 1.너희는 착한 어린이구나.=You guys are good childeren. (In this sentence, I'm not a child./ Children is praised from me ) 2.너희에게 기회를 주겠다. =I'm giving you a chance.( I might be a teacher, professor, parents...who's giving a chane) I wish my answer is helpful for your qustion.

literally - you (plural) colloquially - you guys

"너희" is the plural "you" in korean :D