The rat has many enemies and its greatest enemy is man. Nevertheless, it is the survivor. Although man has16an unending war against them, rats have17the world.In almost every country, from the18cold of the Arctic regions to the unbearable19of the tropics,rats are20thriving, increasing and multiplying. Apart from their ability to21themselves to varying climate conditions, rats possess another22that gives them an advantage in extending their boundaries. More so than most other animals,23snakes, mosquitoes and spiders, they induce fear. Why should this be so? Certainly they carry24and man is slow to forget the Black Plague25killed off millions of people in the fourteenth century. Also, rats have been known to bite26babies, but the number of such attacks is very much exaggerated.One reads27the danger of being attacked by “a cornered rat”，but this belongs to fiction;rats do not28your throat, as many would have us believe.29, it is difficult to believe that its appearance can be a source of30;the common black or brown rat can almost be regarded as a frightful creature while its cousin, the squirrel, is quite pretty and gentle. 

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