Swahili language
The exact number of Swahili speakers, be it native or second-language speakers, is unknown and a matter of debate. Various estimates have been put forward and they vary widely, from 50 million to over 100 million. Swahili serves as a national language of four nations: Tanzania, Kenya, Uganda, and the DRC. Shikomor, the official language in Comoros and also spoken in Mayotte (), is related to Swahili. Swahili is also one of the working languages of the African Union and officially recognised as a lingua franca of the East African Community. South Africa legalized the teaching of Swahili in South African schools as an optional subject beginning in 2020.
Tswana language
Tswana is an official language and lingua franca of Botswana. The majority of Tswana-speakers are found in the north of South Africa, where four million people speak the language and an urbanised variety which is part slang and not the formal Setswana, known as Pretoria Tswana, is the principal language of that city. The three South African provinces with the most speakers are Gauteng (circa 11%) and Northern Cape 
and North West (over 70%). Until 1994, South African Tswana people were notionally citizens of Bophuthatswana, one of the bantustans of the apartheid regime. The Setswana language in the Northwest Province has variations in which it is spoken according to the tribes found in the Tswana culture [Bakgatla, Barolong, Bakwena, Batlhaping, Bahurutshe, Bafokeng to name a few] the written language remains the same. Although Tswana is spoken mostly in South Africa and Botswana, a small number of speakers are also found in Zimbabwe and Namibia; respectively, an unknown number of people and about 10,000 people speak the language there.