英文写法:20 : twenty 、30 : thirty 、40 : forty 、50 : fifty 、60 : sixty 、70 : seventy、80 : eighty、90 : ninety、100 : one hundred百位和千位数字的表达:1、100 = one hundred2、200 = two hundred3、500 = five hundred4、1,000=one thousand5、1,100 = one thousand, one hundred; or eleven hundred6、1,500 = one thousand, five hundred; or fifteen hundred7、2,000 = two thousand8、2,100 = two thousand, one hundred; or twenty-one hundred9、2,500 = two thousand, five hundred; or twenty-five hundred