Perhaps I can help clarify the trouble people are having with past perfect ("had been") vs. simple past ("was").

First, past tense does not necessarily mean that something is no longer true. For instance, I might say "When I was a child, I wanted to grow up fast because my brother was so much older than me." This doesn't mean that my brother is no longer older (thankfully, I still have my brother!). I am just talking about him in a past context. It would be wrong in this case to say "is so much older" just because he is still older.

Second, we don't always need to use past perfect when we have more than one past event. We only use it when the order of those events needs to be clarified or emphasized. For instance, we would say "I was born and raised in California," and not "I had been born in California and then raised there." It's clear enough that being born came first, so there's no need to use the past perfect to clarify. In other cases, we simply don't care which came first. If I say "I have studied French, Spanish, and Russian," I don't need to use "had" to show which came first unless the order is somehow important: "I had already studied French when I started to learn Spanish, so I had an easier time learning vocabulary."

Third, if we are going to use past perfect, we must have a clear time in the past that we are placing our action before. If I say "X had happened," I need to say which past event it preceded, or at what point in the past it had already happened: "X had happened when Y came along" or "By 1850, X, Y, and Z had happened." I was initially going to use "X had happened before Y did," but that's a case that's clear enough without past perfect, so it would be better to use simple past: "X happened before Y did." Notice that dropping "had" from my earlier examples reduces their clarity: "X happened when Y came along." (At the same time? After?) "By 1850, X, Y, and Z happened." (This is not as bad, but it makes it a little less clear that all of these things could have happened at any time before 1850, perhaps even many years earlier.)

Regarding this usage in particular, notice that E doesn't provide any reason to use past perfect. The most simple way to see this is that although we have more than one point in time (the 18th c. and 25 years ago), the main core of sentence does not say that leaching was a method before or by one of those times (the modifier does, but it's not part of the action!). It just says "Leaching had been a method, but until 25 years ago," we didn't know a certain thing about it. When I see "had been a method," I immediately want to know "until what?" The sentence doesn't answer that. On the contrary, it makes it seem that leaching continues--we just know more about it now. Furthermore, even if people stopped using this method, it would still be a method of mineral extraction--it just wouldn't remain in use.

Consider this case:

"Cockroaches had been an insect, but last year, scientists learned more about them." What? Cockroaches had been an insect? Did they stop being an insect and turn into something else? When did this happen? This sentence doesn't make much sense meaning-wise, but it also doesn't meet the criteria for past perfect. We aren't situating one past event in relation to another.

When would "had" be appropriate? Try this:

"By the time the first birds evolved, cockroaches had already been flying for millions of years."
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C it is
A and B miss verb to make first half a clause
D) "that was as early as" is not english
E) misplaced modifier problem. Is it the "mineral extraction" or the "method which is "well-established"?

C) has correct verb-tense agreement and makes "well-established" adjective of proper noun "method"
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Refer the below site to understand the usage of 'had been':

http://www.englishpage.com/verbpage/pas ... nuous.html

IMO:

When we use had been in this sentence it would mean L is a method established in the past and not in use anymore. But the sentence is not trying to make that meaning.

Thanks,
A

please tell me why we eliminated a and b and e and why we went with was form?

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.


Process of Elimination :-

Choice A - 'leaching and it' makes it an error of double subjecting with a single verb
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.
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look at choice B
establish need a object and can not stand without object. it is intransitive verb.

that is why choice B is wrong.

am i correct ?

Hello Bunuel

Kindly underline the question... Thanks
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A. as a method of the extraction of minerals, it was well established
B. as a method of the extraction of minerals well established (fragment)
C. was a well-established method of mineral extraction
D. was a well-established method of extracting mineral that was
E. had been a method of mineral extraction, well established
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thangvietnam Two problems with that:

1) In this context, "established" isn't a verb. It is a past participle modifying "method": the method was well-established by the 18th century.

2) Even if we had a proper verb, it is part of a larger modifier ("as a method . . . century"), so it can't be the main verb. Consider this flawed example:

My parents, who arrived early, but didn't get tickets.

In this case, "arrived" is definitely a verb, but it is part of a modifier adding detail about my parents. It is not part of the sentence core. If we take the modifier out, we have "My parents, but didn't get tickets." This is clearly not a proper sentence, even though it has an additional verb ("get"). We need an action before "but" to justify that conjunction! To fix it, I can just cut "who" and the comma:

My parents arrived early but didn't get tickets.
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That usage is okay. In case it helps, here are a few more examples:

1. The extinction event was thought to have occurred as many as ten million years ago.
2. The website was compromised as early as January 2014.
3. He was considered the most successful player in the league as early as 2016.
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