应该选C吧?as early as +时间 (早在……时候),是正确的表述方法,可以算作是一个固定表达吧?我在不止一个地方听过看过这样的说法。
B缺少was,我觉得应该是Leaching as a method was well established才对。如果没有表示被动态的was,就成了leaching establish,可是establish后面又没有宾语,establish什么呢?而且,让leaching去establish,也不合逻辑吧?
E也不对,well established如果理解成是过去分词的话,那它就是修饰mineral extraction,成了mineral extraction was well established改变了原来的句意;如果理解成是谓语动词的话,又和前面的动词没有连接,成了run-on句型了。
C理解的两种方式Leaching, the recovery of copper from the drainage water of mines,was as early as the eighteenth century a well-established method of mineral extraction ,...
Leaching, the recovery of copper from the drainage water of mines,was a as early as the eighteenth century well-established method of mineral extraction ,...
关键就是这里的时间状语as early as the eighteenth century是修饰动词呢,还是后面的well-established
Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria take an active part in the process.
as a method of the extraction of minerals, it was well established
as a method of the extraction of minerals well established
was a well-established method of mineral extraction
was a well-established method of extracting mineral that was
had been a method of mineral extraction, well established