雅思写作：英文中的倍数如何表达？

　　雅思写作：英文中的倍数如何表达？其实倍数关系是一个我们在小学时候就学习到的知识，但将倍数关系放到英语语境下，我们能够准确识别吗?下面新航道小编就为大家介绍一下相关内容。

　　It is always confusing to use "n times more than" in English. For example, 400 is "three times more than" 100, but 400 is "four times" 100, and 400 is "four times as much as" 100.

　　在英语中, “n times more than”的使用总是令人困惑。例如，400比100多“3倍”，但400是100的“4倍”。

　　让我们来看看猫和老鼠的柠檬问题：

　　Suppose Jerry has 5 lemons.

　　假设Jerry有5个柠檬。

　　Tom has 3 times as many lemons as Jerry.

　　Tom has 3 times more lemons than Jerry.

　　Is there any difference between the following two sentences?

　　我们能知道Tom和Jerry各有多少个柠檬吗?

　　1. Tom has 3 times as many lemons as Jerry.

　　如果Jerry有5个柠檬，那么3 times as many lemons 就是15个柠檬。因此，Tom的柠檬是Jerry的3倍。

　　2. Tom has 3 times more lemons than Jack.

　　Jerry有5个柠檬，Tom的柠檬比Jerry多三倍，那么，Tom有20个柠檬。

　　通过猫和老鼠的柠檬，我们来总结一下这个表达法：

　　A is n times as many as B.

　　A和B的关系就是A=nB

　　A is n times greater/more than B.

　　A和B的关系就是A=(n+1)B

　　在写作中，推荐同学们使用n times as +many/much/形容词+as的表达方式，避免使用 n times bigger/larger/more这种不太好理解、不够直接的表达方式。

　　我们再来看看这些例句:

　　There is ten times as much traffic as in Beijing as in Xiamen.

　　北京的交通流量是厦门的十倍。

　　It cost three times as much as I had expected.

　　花的是我预期的三倍。

　　Joe has three times as much money as Bob has.

　　Joe的钱是Bob的三倍。

　　托福阅读TPO-24《Breathing During Sleep》中有这么一句话：

　　During all phases of sleep, several changes in the air passages have been observed. It takes twice as much effort to breathe during sleep because of greater resistance to airflow in the airways and changes in the efficiency of the muscles used for breathing.

　　这里的倍数关系又是什么呢?

　　反转手机查看文段翻译

　　在睡眠的所有阶段中，气道的一些变化已经被观察到了。睡眠时需要付出两倍的努力去呼吸，因为呼吸道气流的阻力会比较强并且用来呼吸的肌肉的效率会有变化。

　　最后，用一道数学题来检验一下是否掌握了倍数关系了呢?

　　Ana is a girl and has the same number of brothers as sisters. Andrew is a boy and has twice as many sisters as brothers. Ana and Andrew are the children of Emma. How many children does Emma have?

　　(A) 2

　　(B) 3

　　(C) 5

　　(D) 7

　　(E) 8

　　详细解答：

　　Let the number of female children Emma has be n. Since Anna herself is one of them, she has n – 1 sisters. Hence, as given, she must have the same number (= n – 1) of brothers. Hence, the number of male children Emma has is n – 1. Since Andrew is one of them, Andrew has (n – 1) – 1 = n – 2 brothers. Now, the number of sisters Andrew has (includes Anna) is n (= the number of female  children). Since Andrew has twice as many sisters as brothers, we have the equation n = 2(n – 2). Solving the equation for n yields n = 4. Hence, Emma has 4 female children, and the number of male children she has is n – 1 = 4 – 1 = 3. Hence, the total number of children Emma has is 4 + 3 = 7.

　　假设Emma有n个姐妹，因为Anna自己就是其中一个，所以她有n - 1个姐妹。因此，如前所述，她必须有相同的兄弟数(= n - 1)。因此，Emma的兄弟为n - 1。因为Andrew是其中一个，所以Andrew有(n - 1) - 1 = n - 2兄弟。现在，安德鲁的姐妹数(包括安娜)是n(=女孩子的数量)。由于Andrew的姐妹是兄弟的两倍，得到了方程n = 2(n - 2)。因此Emma有4个姐妹，男孩子的数量是n - 1 = 4 - 1 = 3。因此Emma的兄弟姐妹总数为4 + 3 = 7。

　　The answer is (D).

       通过上面的内容，考生们都明白了吗?小编希望大家都能够在雅思考试中取得满意的成绩。