[BR-PT] This is an relatively advanced grammatical concept if you are beginner, but we can try: You use QUÊ: 1. When it is an interjection, ie, when express surprise or amazement feeling. Always with ^ and followed by exclamation point: ● Quê! Conseguiu chegar a tempo? ● Quê! Você por aqui? Note: As interjection, is also used the variation "o quê": O quê! Ela fez isso?! 2. When it is in the end of a sentence, immediately before a point (final, interrogation ou exclamation) or ellipsis: ● Afinal veio aqui fazer o quê? / Você precisa de quê? ● Estamos rindo sem ter de quê. 3. When it is a noun, ie, when it has the meaning of something, anything. Usually is preceed by an article or numeral: ● Sinto um quê de insatisfação. ● Há um quê inexplicável em sua atitude. If it doesn't match with any of this cases is used QUE. "O que" is just a variation.

O que means what . Quê is used when it is an interrogation pronoun without any words afterwards. 'O quê? Você pode repetir?" (What? Can you repeat it?) Que is used with the same function as before, but with a word after that. " O que você disse? Você pode repetir? " (What did you say? Can you repeat it?) Only 'que' without 'o' can be used as 'that or which'. Eu gosto do bolo que minha mãe faz. (I like the cake that my mom makes).