比如我我知道小明6岁,小王5岁。不过我只想表达小明比小王大:
Xiaoming is older than Xiaowang (is).
这个句子是由以下两个简单句复合而成:
Xiaoming is 6 years old.
Xiaowang is 5 years old.
复合方式是:用more来代表两句中的具体数值的相对关系,也就是红色部分合并为一个more,然后more old用older一个词来替换,再用than引导从句,将第二句与第一句连接,再省略掉重复的old,甚至be动词is:
Xiaoming is older(=more old) than Xiaowang (is old省略).
如果这里你能理解,那么来看这么个例子:
比如专家在去年时预测今年通胀率是3.0%,但今年我们实际发现是5.0%。先把两个简单句表达出来:
The inflation rate is 5.0%.
It was previously thought that the inflation rate would be 3.0%.
按照同样的规则,我们将两句复合:把5.0%和3.0%用higher来合并替换再把后句用than与前句相连,得到这样一句:
The inflation rate is higher than it was previously thought that the inflation rate would be
The inflation rate is higher than was previously thought.
当然,这个was是be动词也可以省略,于是也可以是这个形式:
The inflation rate is higher than previously thought.
可能你会纠结:it指代the inflation rate不可以么?然后句子写成这样:
The inflation rate is higher than it(the inflation rate) was previously thought.
我们反过来推理一下,假如是这样,那这个比较状语从句是由哪两个句子复合而来的呢?按照前面的结构反推,理论上应该是这样两个句子:
The inflation rate is 5.0%. The inflation rate was previously thought 3.0%.
→The inflation rate is higher than it was previously thought.
但是我们知道,think在被动情况下,可以跟to be做宾补,也就是说下面这句是可以的: The inflation rate was previously thought to be 3.0%.
而如果将这句和主句合并,复合成的句子就是对的:
The inflation rate is higher than it was previously thought to be.
你会发现,假如非得用it指代inflation rate,那加一个to be就对了。
原理有一些复杂,不过有一个辅助理解的方式供你参考。简单来说,人们原本thought了的是“inflation rate would be 3.0%”这个命题或者说这件事,而不是thought了“inflation rate”这么一个名词概念,所以inflation rate要和be同时出现(it was previously thought to be),要么干脆就整个命题省略(was previously thought)
这个结构,OG里就专门考到过2次,prep里更是很多。我们小结一下,正确的几个用法: 1. The inflation rate is higher than previously thought.
2. The inflation rate is higher than was previously thought.
3. The inflation rate is higher than the economists previously thought. (这就是被动换主动了)
4. The inflation rate is higher than it was previously thought to be.
常见的错误用法:
1. The inflation rate is higher than it was previously thought(没有to be).
2. The inflation rate is higher than the economists previously thought it.(对think这个动词而言,主动用法加to be也错,你查词典就能看到think+to be只用于被动,不过如果换成predict/require之类的动词,是有加to be的主动用法的,这是个小的细节)
1. The medicine is more effective than (was) expected.
2. The house was more luxuriously decorated than suited his taste.
3. She is prettier than I could imagine.
4. He works as hard as his boss requires.
5. Never give him more money than (is) necessary.