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题库 / Prep2008E2-SC-196
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
请看讲解视频
①错选A...完全是读了后边忘了前边...A中的it是出现了的第二个主语啊...
②第一遍的时候错选了E...以为自己考虑到了时态问题...其实就是没有读清楚题目含义啊！！！（真要命）
③recovery ：~ (of sth/sb) 找回 重新获得 the recovery of the missing diamonds 丢失钻石的寻回
~ (from sth) 恢复正常状态 make a quick, speedy, good, slow, etc recovery (from illness)
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