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 took 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
What does this question test?
This question tests your ability to analyze the sentence structure and identify all SV pairs. It also tests your understanding of the verb tenses to ensure that you reject answer choices that do not communicate the intended meaning of the sentence.
What does the sentence mean?
This sentence talks about “leaching”. It first defines the term “leaching”. It is recovery of copper from the drainage water of mines. It then states that this is well established method of extraction of minerals even in 18th century. Then the sentence brings up a paradox, stating that despite this process being so old, only 25 years back miners realized that bacteria took an active part in this process.
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What are the errors in the original sentence?
Here is the sentence structure of this sentence:
- Clause 1: Leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals,
- Clause 2: it was well established as early as the eighteenth century,
- Clause 3: but until about 25 years ago miners did not realize
- Clause 4: that bacteria took an active part in the process.
Clause 1 does not have any verb. The subject “leaching” does not have any verb. Thus this sentence is a fragment. In addition, clause 2 is not connected appropriately to clause 1. It should be connected using a ; or ,FANBOYS.
Answer Choice Analysis
Choice B – Fragment Error: This choice changes clause 2 into a modifier. But it does not address the absence of verb for the subject “leaching”.
Choice C – No errors.
Choice D – Modifier error: The sentence implies that well-established method of mineral extraction was as early as 18th century. This is non-sensical – saying that a method was as early as 18th century. It would have made sense if this said that the method existed as early as 18th century. This error may be construed as SV-Make sense error – the subject – “well established method” does not make sense with the verb – “was”.
Choice E – Verb error: This choice states uses past perfect tense for the verb – had been. This changes the intended meaning of the sentence. This sentence now implies that leaching is no longer a method of mineral extraction. In the light of this information, what follows does not make sense. Since this is no longer a method of mineral extraction, the fact miners realized its working 25 years back becomes invalid. Thus, because this sentences uses past perfect tense as shown, it distorts the intended meaning of the sentence.
Thus, the correct answer is Choice C.
What are the key take-away messages?
- In a sentence make sure that all SV pairs are accounted for.
- Select the choice that communicates the intended meaning of the sentence.
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