Why is America compared to a melting-pot?

Why is America compared to a melting-pot? Why Mark Twain is a Mirror of America? Why Mark Twain is a Mirror of America why is America the most powerful country?用英文回答 this is why america is now starting to fithis is why america is now starting to fight back against the fast food companies翻译 This is why America is now starting to fight back against the fast food companies. compared with the america,russia is the worst friend?compared with the america,russia is the worst friend,why should we call them big brother and licktheir asses? Canada is in( ) America 填空：That is____fast foodis so popular in North America.选项A how B what C when D why why America have cutting- edge technology Why is That is why fast food is so popular in North America.People spend about 40% of their money on fastfood.的翻译 A toda madre,Compa Bill is form America,he is a America boy.改错 she is from America是什么意思 Jack is from america.翻译 America is in south of____ she is leaving( )China( )America