double English knotted netting

例句：

1. 1. The price of the product has doubled since last year.
   该产品的价格自去年以来翻了一番。
2. 2. He doubled his savings to buy a new car.
   他加倍了他的储蓄来买一辆新车。
3. 3.She doubled her efforts in preparing for the exam.
   她在准备考试时加倍努力。