Learn Portuguese (Portugal): Ouvimos dizer que vais casar. É verdade? - We heard you are getting married. Is it true?

While Ouvimos que is sometimes used, ouvir dizer que is the highly idiomatic, standard way to say "to hear (through the grapevine) that" in Portuguese. You use this fixed phrase whenever you receive news or rumors. Without dizer, it sounds a bit more like you physically heard a noise rather than learned a piece of information.

Shouldn't it be vais casar-te since the verb casar is often reflexive?

In European Portuguese, casar is frequently used without the reflexive pronoun when you are simply referring to the general event of getting married, as seen in this sentence. You generally only need the reflexive pronoun (and the preposition com) when specifying who someone is marrying, such as Vais casar-te com o João? (Are you marrying João?).

Why use vais casar instead of the future tense casarás?

Using the verb ir plus an infinitive (vais casar) is the most natural way to express planned or near-future events in everyday spoken Portuguese, directly mirroring the English "going to get married". The actual future tense (casarás) sounds much too formal and literary for a casual conversation between friends.

Why do we use É (from ser) in É verdade? rather than Está (from )?