主要有3种句型： 1.倍数+as+much/many/long/big等+as 如：The room is three times as large as that one. 这个房间是那个房间的3倍大. 2.倍数+longer/larger/more等+than 如：The room is two times larger than that one.(意思同上) 3.表示变化的动词+by+ 百分比 如：Populationhas increased by 200% in the past25 years. 人口在过去的25年里增加了2倍（是原来的3倍）
