How do you say stop talking Russian in Russian?

There are a few ways to say "stop talking Russian" in Russian, depending on the context and the desired level of politeness:

Formal:

* Перестаньте говорить по-русски. (Perestaňte govorit' po-russki.) - This is the most formal and polite way to say it, suitable for addressing someone of higher social status or in a professional setting.

* Прекратите говорить по-русски. (Prekratíte govorit' po-russki.) - Similar to the previous phrase, but slightly stronger and less polite.

Informal:

* Хватит говорить по-русски! (Khvatit govorit' po-russki!) - This is a more direct and less polite way to say it, suitable for friends or family.

* Не говори по-русски! (Ne govori po-russki!) - This is the most informal and blunt way to say it, and should only be used with people you know well.

Note: The context is crucial. If you are asking someone to stop talking Russian in a specific situation, you can use a phrase like:

* Можно говорить по-английски? (Mozno govorit' po-angliyski?) - Can we speak English?

* Давайте поговорим на английском. (Davaite pogovorim na angliyskom.) - Let's talk in English.

It's always important to be mindful of the situation and your relationship with the person you are addressing when choosing the appropriate way to say "stop talking Russian."