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Bunuel
Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.

(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.
(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.
(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which aredug during the Greenwood copper boom a century ago.


 


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The correct answer is (D): The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.

This sentence is in the active voice and uses the past tense. The verb are is used in the plural form to agree with the subject hundreds of copper mines. The phrase most of them is used to modify the noun copper mines and indicates that most of the mines were dug during the Greenwood copper boom.

The other options are incorrect because:

(A) uses the passive voice, which is less concise and less forceful.
(B) uses the present tense, which is not correct for a past event.
(C) uses the word dotting, which is not a strong verb and does not accurately convey the image of the hills being covered with copper mines.
(E) uses the word dug in the past participle form, which is not correct for a main verb. The past participle form of dig is dug, but it is used as an adjective in this sentence. The correct form of the verb is dig.
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A is out because of the wrong modifier that modifies the hills
B is out because of the same reason above.
D is out becuase the latter part lack the verb
between c and e, e seems to make sense
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Bunuel
Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.

(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.
(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.
(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which aredug during the Greenwood copper boom a century ago.


 


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A- Misplaced Modifier, After comma, there should be someone who dug during the greenwood copper boom...
B- Correct
C- During denotes period of time which is finished already. So, are dotting is wrong here
D- Ambiguous use of them, it's mines or hills? not clear. Also, main verb is in non-essential part which makes the sentence fragments
E- Ambiguous use of which. Also, main verb is in non-essential part which makes the sentence fragments
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A - Modifier issue - hills were not dug, mines were dug
B - Same as A. Meaning is wrong due to modifier issue.
C - Subject and verb are too far apart - there could be a better structure. Also, dotting the hills - tense issue, sentence seems to say that mines are dotting the hills even now.
D - Modifier correctly placed, tense correctly used.
E - Simple present tense used "are" which is distorting the meaning.

Therefore, option D is the correct answer.

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Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.


- meaning - the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, and these mines were dug during the Greenwood copper boom


(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
- modifier error


(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.

- modifier error

(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.

- meaning error - hundreds are dotted



(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
- Meaning error
- mines did digging


(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which are dug during the Greenwood copper boom a century ago.

- Correct
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(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
Incorrect. Many of them dug during the Greenwood copper boom a century ago - acts as a modifier and modifies the noun that comes after the comma , i.e, hills. But as per context of sentence, hills were not dug , mines were dug.

(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.
Incorrect. Same error as (A). Dug during the Greenwood copper boom a century ago - acts as a modifier and modifies the noun that comes after the comma , i.e, hills. But as per context of sentence, hills were not dug , mines were dug.

(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.
Incorrect. This choice correctly uses the modifier to modify mines. But the use of present continuous tense is incorrect. We use the present continuous to talk about something temporary. But the mines have been in existence since a century and thus we cannot say that their existence is a temporary phenomenon.

(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
Correct. This choice correctly uses simple present tense to describe a fact( Hills are dotted with hundreds of copper mines) and correctly places the modifier (copper mines, most of them dug during the Greenwood copper boom a century ago.)

(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which are dug during the Greenwood copper boom a century ago.
Incorrect. This choice incorrectly uses present tense to describe something that has been completed in the past. For completed past events, past tense needs to be used.
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Meaning is important - If we read the whole sentence then it were the mines that were dug and not the hills so A and B are out.
C is out because 'mines are dotting... ' is illogical and doesn't make any sense.
E has the tense error - we cannot use 'are' along with a century ago.
D rules out this tense error and hence the answer
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Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.

(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.
(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.
(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which aredug during the Greenwood copper boom a century ago.

Explanation:
(B) "many hundreds" is a redundant expression. Rejected.
(C) "Most of them" changes the meaning.
(D) "Most of them" changes the meaning.
(E) "Most of which" changes the meaning.

(A) correctly addresses the message of the sentence. Hence, ANSWER (A)
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Dangling modifier - confused between most of them vs most of which for choices d and e
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B is the answer.

A- ‘many of them’ is awkward.
C - ‘are dotting the hills’ is wrong.
D- not sure if ‘them’ refers to mines or hills.

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My Answer: D

Option A: The hills are not dug, the copper mines are.
Option B: Same reason as A.
Option C: Mines are dotting is awkward usage.
Option D: Its correct.
Option E: are dug is not the correct tense usage. They were dug in the past not in the present.
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Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.

(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.
Incorrect modifier usage; it is not the hills which have been dug, rather it is the copper mines.

(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines.
Same reason as above; Incorrect modifier usage; it is not the hills which have been dug, rather it is the copper mines.

(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona.
use of present continuous tense is incorrect; Not a progressive action at present.

(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.
Modifier usage for copper mines is correct ; Use of past tense to show the copper mines dug a century ago is appropriate.

(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which are dug during the Greenwood copper boom a century ago.
Modifier usage for copper mines is correct; however, the Use of present tense to show the copper mines dug a century ago -- a past action---is inappropriate.

(D) is the CORRECT answer
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A) This answer choice suggests that the modifying phrase 'Many of them dug during the greenwood copper boom' modifies the immediate noun 'hills' which does not makes sense. what clearly makes sense is that the copper mines are dug in the hills. Hence, A is incorrect.
B) Same as in A, this option choice is still referring that the hill was dug during the boom. Hence B is incorrect.
c) This choice clearly indicates that 'hundreds of copper mines' were dug during the boom, but the present continuous verb 'dotting' creates confusion that the mines are still being dug and are covering the hill as we speak. Dotted would be the correct tense form to use.
d) This choice clearly indicates that the 'mines' were dug during the boom and 'the hills' were dotted with mines. Hence, D is correct choice
e) This option uses the wrong tense 'are' in 'most of which are dug during the ...'. The mines were dug in the past, so the right way to say would be most of which were dug
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Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines.

(A) Many of them dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines. - meaning issue (What was dug? Hills? No.)
(B) Dug during the Greenwood copper boom a century ago, the hills to the east of Death Valley, Arizona, are dotted with many hundreds of copper mines. - meaning issue (What was dug? Hills? No.)
(C) Hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago, are dotting the hills to the east of Death Valley, Arizona. - are dotting (time sequence/incorrect tense)
(D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago. - correct
(E) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of which are dug during the Greenwood copper boom a century ago. - TENSE issue
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The correct answer is: (D) The hills to the east of Death Valley, Arizona, are dotted with hundreds of copper mines, most of them dug during the Greenwood copper boom a century ago.

The sentence structure in option (D) is the most clear and grammatically correct one. It provides a concise and coherent statement about the copper mines in the hills to the east of Death Valley, Arizona, and their association with the Greenwood copper boom.
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Option A and Option B mean that the hills are dug, which gives an inappropriate meaning. Option C means that the hills are dotting the mines which is meaningless. Option D and E give correct meaning but option D don't have a finite verb. Hence option E.
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Is it D? The sentence structure is the most sound amongst all the other choices.
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