Chechens
In 1989, 73.4% spoke Russian, though this figure has declined due to the wars for a large number of reasons (including the lack of proper education, the refusal to learn the language, and the mass dispersal of the Chechen diaspora due to the war). Chechens in the diaspora often speak the language of the country they live in (English, German, Arabic, Polish, Georgian, etc.).
Teip
Historically, if non-Chechen minorities living in Chechen lands wanted to take part in the political processes of the Chechen nation, and integrate into it, they would request admittance as an ethnic teip. They would continue, for a time, to speak their other languages, but also learned Chechen. Due to the encouragement of teip exogamy, as the generations passed, they would come to be heavily intermarried into the Chechen nation and as a result, be slowly Chechenized culturally and linguistically. The level of Chechenization varies between these foreign-origin teips, with some well-preserving their cultural traits and others not. They are nonetheless known as impure teips (not in a derogatory sense), for their foreign origin. Their loyalty to the nation is not any more in question than a Chechen-origin teip.