Jura?

Use it as a one-word question. Your intonation does all the heavy lifting here. A rising pitch at the end makes it a genuine question. A flat, deadpan delivery makes it sarcastic. It is incredibly versatile and fits almost any conversation.

Use it when a friend tells you they won the lottery. Use it when your mom says it might rain later. It works perfectly in text messages to show you are listening. It is the ultimate social lubricant in Brazil and Portugal. It keeps the conversation flowing without you having to say much.

Avoid using it in very solemn or tragic situations. If someone shares bad news, jura? might sound dismissive or skeptical. Do not use it with your boss during a performance review. It is a bit too casual for high-stakes professional settings. You do not want to sound like you are doubting a superior's authority.

Lusophone cultures are very expressive and social. People love to react loudly to stories to show engagement. Jura? is a remnant of a more religious past where oaths mattered. Today, it is just a reflex. It is so common that people often say it even when they totally believe you. It is just a way of saying, "Wow, tell me more!"

In Brazil, you might hear Sério? which is more neutral. You will also hear Mentira! which literally means "Lie!" but is used exactly like "No way!". If you want to be extra emphatic, you can say Jura por Deus? (Swear by God?). For a very slangy version, young people might just use Papo reto? to ask if the talk is straight.