How do you say how many brothers or sisters have in french?

You can ask how many brothers or sisters someone has in French using these phrases:

Formal:

* Combien avez-vous de frères et sœurs? (How many brothers and sisters do you have?)

* Combien de frères et sœurs avez-vous? (How many brothers and sisters do you have?)

Informal:

* Combien de frères et sœurs tu as? (How many brothers and sisters do you have?)

* Tu as combien de frères et sœurs? (How many brothers and sisters do you have?)

You can also use separate questions for brothers and sisters:

* Combien de frères as-tu? (How many brothers do you have?)

* Combien de sœurs as-tu? (How many sisters do you have?)

Remember to adjust the verb conjugation based on the person you are talking to (formal "vous" or informal "tu").