“亿以内数的读法和写法”是建立在“万以内数的读法和写法”基础上的，是多位数认识的又一次推进。教学时，必须在复习原有知识的基础上，有序地落实每一个知识点。一、在数数中建立新的计数单位，在观察数位顺序表中明确四位分级的方法在复习“10个一是十……10个一百是一千 The “method of reading and writing hundreds of millions of words” is based on the principle of “reading and writing within one million.” It is another promotion of multi-digit understanding. Teaching, we must review the original knowledge, based on the orderly implementation of each point of knowledge. First, the establishment of a new counting unit in the number of observations in the digital sequence table clear four-graded approach in the review of "10 one ten ... 10 one hundred is one thousand