Swahili is spoken by various ethnic groups that inhabit several large stretches of the Indian Ocean coastline from southern Somalia to northern Mozambique, including the Comoros Islands. Although only 5-10 million people speak it as their native language, Swahili is also a lingua franca of much of East Africa and the Democratic Republic of the Congo, is a national or official language of four nations, and is the only language of African origin among the official working languages of the African Union. Swahili is a Bantu language that serves as a second language to various groups traditionally inhabiting parts of the East African coast. About 35% of the Swahili vocabulary derives from the Arabic language, gained through more than twelve centuries of contact with Arabic-speaking traders. It also has incorporated German, Portuguese, English and French words into its vocabulary through contact during the last five centuries. Swahili has become a second language spoken by tens of millions in three countries, Tanzania, Kenya, and Congo (DRC), where it is an official or national language.

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