Learn French: Est-ce que tu vas te marier bientôt ? - Are you going to get married soon?

In the near future tense, you use a conjugated form of aller (here, vas) followed by an infinitive. When using a reflexive verb like se marier (to get married), the reflexive pronoun (te) must go directly before the infinitive verb it belongs to, not before the helping verb aller.

Why is the word te needed here? Can I just say tu vas marier?

In French, the verb for 'to get married' is reflexive: se marier. Without the reflexive pronoun, marier means to perform a marriage ceremony for someone else (like a mayor or priest would do). To say that you are the one getting married, you must use the reflexive pronoun that matches the subject tu, which is te.

Could I ask this question without using Est-ce que?

Absolutely! In casual spoken French, you can just state the sentence and raise your voice at the end: Tu vas te marier bientôt ? Using Est-ce que is just a standard, foolproof way to make it clear you are asking a question right from the start.

Why does bientôt go at the very end of the sentence?

In French, adverbs of time like bientôt (soon), demain (tomorrow), or tard (late) typically go at the very end of the sentence or clause. They almost never interrupt the aller + infinitive structure of the near future tense.