What language do they speak in Tanzania?

Tanzania is the most linguistically diverse country in Africa. It’s home to over 100 languages, split
amongst the country’s 120 different ethnic groups. In an effort to make sure that no one tribe
dominates in the country, there is no de jure official language.
However, Swahili is the National Language of Tanzania and is spoken by a large percentage of
the population. English is used as a de facto language in Tanzania and is a remnant of colonial
rule. You’ll find most people can speak and understand it in the cities, but it’s not widely spoken in
the rural areas.