Complex sentence: Johannesburg (;; also known as Jozi, Jo'burg, Joni, eGoli, and abbreviated as JHB) is the largest city in South Africa and is one of the 50 largest urban areas in the world.
Split into simpler sentences: Johannesburg (;; also known as Jozi, Jo'burg, Joni, eGoli, and abbreviated as JHB) is a large metropolis and the largest city in South Africa. The city is one of the 50 largest urban agglomerations in the world.