1) Plains are formed when everything in the land weathered or eroded away,leaving the land flat.
and
2) Another way is when volcano erupt ,and burn everything in its way,all that is left are the plains,This makes bare land or barren plains.
The most common are from dried up lakes or a glacier moving past an area.
yes it is right according to my research
Keywords are the significant words or phrases that define the topic of an essay question. A synonym on the other hand is a word or phrase that means exactly or nearly the same as another word or phrase
The statement that a synonym for a word may be included as a keyword is true, because using synonyms will get you a more complete set of search results.
The Sahel Region is the region that borders between the Sahara Desert to the North and Sudanian Savannah to the South. The countries which are known to traditionally make up the Sahel region are the Gambia, Senegal, Mauritania, Mali, Burkina Faso, Algeria, Niger, Nigeria, Cameroon, Chad, Sudan, South Sudan and Eritrea. Although the entirety of these countries are not considered all to fall within the Sahel Region.