 
 <prompt> Wetin be di savannah wey get di highest grass? Based on di previous question, write a context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: Eberyting wey dey between far south and far north na savannah (wey no get plenti tree, na grasses and flowers dey between trees). Rainfall dey limited, between 500 and 1,500 millimetres (20 and 60 in) per year. The three categories of savannah zone na Guinean forest-savanna mosaic, Sudan savannah, and Sahel savannah. Guinean forest-savanna mosaic na plains wey get tall grass wey dey interrupt by trees. Sudan savannah dey similar but e get shorter grass and shorter trees. Sahel savannah na patches of grass and sand wey dey for northeast. For Sahel region, rain dey less than 500 millimetres (20 in) per year and Sahara Desert dey move closer. For dry north-east corner of di kontri dey Lake Chad, wey Nigeria dey share with Niger, Chad and Cameroon. 