求助NN-GWD-17-Q18

zhushanyi

（1）     GWD-17-Q18

Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

 

1. Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.
2. Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.
3. With charcoal’s being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.
4. The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.
5. Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.

不明白,A中并列一定不平行,为什么对呢?D我把它当因果的独立主格,不行么?

Zeldaw

A中为什么一定不平行呢？在A中and前后各一个原因，在逻辑上是完全成立的。不是说一定要because ...and because 才是平行，当然这样更加的整齐，更加的GMAT

zhushanyi

恩，那么Ｄ怎么解释呢

Zeldaw

我认为D的前半句很别扭，是一个名词短语，不能构成独立主格