描写今昔对比时要根据过去的情况和现在的事实组织材料。这类书面表达的一般写作格式为：
1．开头提出主题句(提出什么事情发生了变化)
2．对过去情况的描述(用过去时态， 主要是一般过去时)
3．对现在情况的描述(用现在时态， 主要是一般现在时)
4．总结句
增分佳句
1．Our school/hometown, as all may know, is not what it used to be.
2．Great changes have taken place in my hometown in the last five years.
3．Two new buildings have been built and are in use.
4．Now, a large number of trees have been planted, which hold the soil and water.
5．I believe that the life of the peasants will get better and better.
