例句：
In those days most people left school when they were only fifteen years old.
那時(shí)候，大多數(shù)人上學(xué)只上到十五歲。
The wiring in your house should be renewed every ten to fifteen years.
你家里的電線應(yīng)該每十到十五年更新一次。
The room measures fifteen feet by twenty feet.
房間15英尺寬20英尺長(zhǎng)。