3、倍數的表達方式

　　Double 是兩倍/大一倍

　　Increase/decrease three times 增長/減少了三倍

　　4、大約的表達方式

　　About/around + 數字

　　數字 + or so

　　Approximately + 數字

　　5、常用的小作文的趨勢句式表達

　　句式一: 變化主體/圖畫中主體+趨勢動詞+副詞+時間區間

　　Eg: The number of aged people over 65 increased significantly from 1940-2000.

　　The number of aged people over 65 dropped slightly from 1960-1980.

　　The number of aged people over 65 fluctuated between 1 million and 1.2 million from 1940-1950.

　　The number of aged people over 65 remained stable from 1930-1940.

　　句式二: There be + 形容詞 + 表示趨勢的名詞 + in+ 變化的主體+ 時間區間

　　Eg: There was a significant increase in the number of aged people over 65 from 1940-2000.

　　There was a slight decline in the number of aged people over 65 from 1960-1980.

　　There was a fluctuation between 1 million and 1.2 million from 1940-1950.