OG12 037 三点疑问

第二，B中economical表示经济的，节约的，节俭的，与economic意思不同。要说经济发展之类的用economic，说“买这辆车很经济很实惠之类的用economical。

首先，A中第一个it不是形式主语，就是指代的 schistosomiasis ，第二个也是的。表示  它能使人变得很虚弱，所以成为了很多发展中国家财政支出的大头。也就是schistosomiasis is so debilitating that it has become an economic drain on many developing countries.
如果是形式主语的话，it is ....that是可以去掉而不影响句子意思的。在这里显然不是。


第三点，我查了下manhattan老师的回答，他说这里不能用倒装，句子顺序很poor

第二点中   it is so debilitating 是它能使（人）虚弱
而   it is of such debilitation 的意思是：它是如此虚弱
be+of+名词  修饰某个词等于该名词的形容词形式修饰某个词
for example, "the flower is of such beauty" is equal to "the flower is very beautiful". in this case, "beautiful" modifies "flower".
that is to say, in the " it is of such debilitation " case, the quoted part means "it is debilitated", and "debilitated" is different from "debilitating", because the former one means "weak" while the latter one means "weakening" .