C. Complete the sentences. Smile S ① Sudan is the third biggest (big) country in Africa. ② The Nile is the longest. (long) river in the world. ③ The. hottest (hot) temperatures are usually in the north of Sudan. 4) The highest (high) mountain in Sudan is in Darfur.. (5) Omdurman is the largest (large) city in Sudan. The Nubian Desert is one of the biggest (big) deserts in Africa.