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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.

A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating - awkward and not parallel
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat - wrong parallelism
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat - awkward
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating - parallel and conveys the meaning
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat - awkward
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A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating -- heating is not || to generation of electricity -- correct form generating
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat -- to heat is not || to be generated
efficiently -- correct form to generate
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat -- to heat is not || to for generating
correct form to generate
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating -- for heating is || to for generating --right answer
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat -- heat is not || to generation of electicity -- correct form heat || generate
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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.
A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat
here is parallelism error.The parallel structure is enough for...............and for...........
Only option d follow the parallel structure enough for...............and for...........
Thus D is the correct answer
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Hi,

Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes

A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat



In the above question :

The actual sentence has problem in modifier as enough of minning heat and producing energy does not make sense ,we need something that says energy produced ,which is enough for efficient generation of electricity and heat .

So based on this analysis we have only two choices D,E .

Now in choice D :

something is done to produce energy , and that energy is enough for generating electricity efficiently and for heating

I agree that this choice maintains parallelism , but here the modifer efficiently is used only for electricity but not for heat .

Hence I eliminated this choice

In Choice E :

something is done to produce enough energy for efficient generation for electricity and heat

The problem with this sentence is that it changes the meaning by saying something is done to produce enough energy (i.e not energy but enough energy), but the other problem related to modifier in the 2nd part of this sentence -"efficient generation of electricity and heat"-has been rectified .


My question is how to choose between the above 2 choices .
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this is a very good || ism question.

I had gone thru one of RON's videos and he had taken this question as an example to explain ||ism.

The main situation here is to get idea what the question means.

1)Scientists ...... have succeeded for the first time......"to" produce energy on a commercial scale

now the question arises for what???????

the idea conveyed following this should be parallel
2)it means that the energy produced will be used "for generating electricity" and" for heating" factories and homes.

So option D is concise and conveys the idea perfectly.


hope it helps.
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Even in the original sentence, there are two things being accomplished by energy:

1. Efficient generation of electricity
2. Heating factories and homes

So, D is not changing the meaning of the original sentence.

E has a classical parallelism issue. The right side of and has heat. So, there must be something on the left side of and that is parallel to heat. What is on the left side of and that is parallel to heat? Let’s look at the sentence with choice E:

Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior to produce enough energy on a commercial scale for efficient generation of electricity and heat factories and homes

Well, on the left side, the closest entity parallel to heat is produce!! So, E has the following meaning:

Scientists have succeeded in mining heat from the Earth’s interior to:

1. produce energy for efficient generation of electricity and
2. heat factories and homes

At the very least, the meaning portrayed above is a deviation from the intended meaning, which is:

Scientists have succeeded in mining heat from the Earth’s interior to produce energy enough for:

1. generating electricity efficiently
2. heating factories and homes
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Hi,

Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes

A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat



In the above question :

The actual sentence has problem in modifier as enough of minning heat and producing energy does not make sense ,we need something that says energy produced ,which is enough for efficient generation of electricity and heat .

So based on this analysis we have only two choices D,E .

Now in choice D :

something is done to produce energy , and that energy is enough for generating electricity efficiently and for heating

I agree that this choice maintains parallelism , but here the modifer efficiently is used only for electricity but not for heat .

Hence I eliminated this choice

In Choice E :

something is done to produce enough energy for efficient generation for electricity and heat

The problem with this sentence is that it changes the meaning by saying something is done to produce enough energy (i.e not energy but enough energy), but the other problem related to modifier in the 2nd part of this sentence -"efficient generation of electricity and heat"-has been rectified .


My question is how to choose between the above 2 choices .

Thanks,
Deepak

Hi,

Let me write the original sentence again.

    • Scientists at the Los Alamos National Laboratory have succeeded for the first time in
      o mining heat from the Earth’s interior and
      o producing energy on a commercial scale, enough for
         efficient generation of electricity and
         heating factories and homes.

In the original sentence, “efficient” is modifying only “generation of electricity”.
This is because it is non sensical to say that mining heat and production of energy provide efficient heating at homes.
Similarly the original sentence only conveys “generation of electricity”.
“heating homes and factories” is not connected to the “generation” part.
So “efficient generation” and “heating” are parallel in this sentence.

The error in this sentence is the representation of “mining” and “producing” as separate independent entities. (As you have mentioned).
Choice D appropriately rectifies this error.

Now let us look at the whole sentence with choice E.

    • Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior to produce enough energy on a commercial scale for efficient generation of
      o electricity and
      o heat
    factories and homes

Can you see that there is a dangling noun at the end without any proper connection?

This is a very obvious error and can be used as a strong reason to eliminate option E, even if you understood the meaning in a different sense.

Hope this helps! :)

Regards,
Krishna
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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes

This is purely a parallelism play and one needn’t go farther.

A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating --- 1. It should be in mining and in producing; 2.it should be ‘generation of and ‘heating of’ to be parallel
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat--- 1. in mining and producing is wrong as in A. 2.-- for electricity to be generated efficiently and to heat---un//.
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat --- --- for generating electricity efficiently and to heat --- un//.

D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating --- good--
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat --- for efficient generation of electricity and heat--- un//
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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.
A. and producing energy on a commercial scale, enough for efficient generation of electricity and heating
B. and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat
C. for energy production on a commercial scale, enough for generating electricity efficiently and to heat
D. to produce energy on a commercial scale, enough for generating electricity efficiently and for heating
E. to produce enough energy on a commercial scale for efficient generation of electricity and heat

ans D
We should first concentrate on the intended meaning, it's not the first time energy would be produced on a commercial scale. So we can eliminate A and B.
option C: for generating .... to heat is not parallel
option E: heat factories and homes doesn't sound good
Option D: for generating and for heating parallel and correct
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Answer: D

A. Incorrect. Parallelism and logic issue.

Parallelism issue:
Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and (succeeded in) producing energy on a commercial scale, enough for efficient generation of electricity and (efficient generation of) heating factories and homes.

Alternate interpretation:
Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and (succeeded in) producing energy on a commercial scale, enough for efficient generation of electricity and (efficient) heating factories and homes.

Logic issue: Realistically, the events aren't mutually exclusive. The scientists could have succeeded at mining heat for the first time and also succeeded at producing electricty on a commercial scale for the first time at the same time, but in reality the logic suggests that they succeeded at one event: mining heat to produce electricity on a commercial scale for the first time.

B. Incorrect. Parallelism and logic issue.
B. Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing enough energy on a commercial scale for electricity to be generated efficiently and (for) to heat factories and homes.

C. Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior for energy production on a commercial scale, enough for generating electricity efficiently and to heat factories and homes.


C illogically states that energy production is what is enough for heating factories and homes when it should be the energy itself.

Preposition paired with an infinitive raises eyebrows also


D. Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior to produce energy on a commercial scale, enough for generating electricity efficiently and for heating factories and homes.

D ammends earlier issues


E. Incorrect.
Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior to produce enough energy on a commercial scale for efficient generation of electricity and (for) or (generation of) heat factories and homes.
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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.

Test Points: Parallelism & Scentence Structure

(A) and producing energy on a commercial scale, enough for efficient generation of electricity and heating ("efficient generation of..” is a noun phrase, "heating...“ is a verb phase, this structure violates parallelism)

(B) and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat (Active+and+Passive structure which violates parallelism)

(C) for energy production on a commercial scale, enough for generating electricity efficiently and to heat ("for generating" and "to heat" constitute a structure which violates parallelism)

(D) to produce energy on a commercial scale, enough for generating electricity efficiently and for heating

(E) to produce enough energy on a commercial scale for efficient generation of electricity and heat (same reason as A)
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Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing energy on a commercial scale, enough for efficient generation of electricity and heating factories and homes.

(A) and producing energy on a commercial scale, enough for efficient generation of electricity and heating -> succeeded and producing are not parallel. Incorrect.

(B) and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat -> Same error as A. Incorrect.

(C) for energy production on a commercial scale, enough for generating electricity efficiently and to heat -> for generating...and to heat are not parallel. Incorrect.

(D) to produce energy on a commercial scale, enough for generating electricity efficiently and for heating -> This is better. Let's keep it.

(E) to produce enough energy on a commercial scale for efficient generation of electricity and heat -> We have again parallelism error between efficient generation of electricity and heat. Incorrect.

So, I think D. :)
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in choice B means

producing energy for electricity
to be generated
and
to heat factories

producing energy for electicity to heat factories is meaningless.
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egmat DmitryFarber GMATNinja

Couple of questions regarding this question:

1) For choice D, is "enough for generating...." a noun modifier modifying "energy"? Or is it a prepositional phrase that is a verb modifier modifying the verb "produce"? Because logically I think it should modify "produce", but then how can the noun modifier "enough for generating...." jump over a verb modifier to modify the noun "energy"? Isn't there a rule saying that noun modifiers can only jump other noun modifiers?
2) For choices B and C, why are the following constructions not parallel?

B: "enough... for electricity to be generated and to heat factories and homes."
C: "enough for generating electricity and to heat factories and homes."

For me, both these constructions are:

Scientists have succeeded in producing energy, energy that is "enough for X and (enough) to do Y". Therefore, it's parallel because the construction is "enough (prepositional phrase) and enough (prepositional phrase). Is my understanding incorrect? If it is correct, how is this not parallel? If it's not correct, why is this not parallel?

3) For B, is there a meaning ambiguity issue where "to heat" could be parallel to either "to be generated" or "for electricity..."?

4) For C, why is there a meaning error when "enough for generating..." is modifying "energy production" instead of just "energy"? Isn't it also logical to say that "energy production" is enough to generate electricity efficiently?

Thank you!
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egmat DmitryFarber GMATNinja

Couple of questions regarding this question:

1) For choice D, is "enough for generating...." a noun modifier modifying "energy"? Or is it a prepositional phrase that is a verb modifier modifying the verb "produce"? Because logically I think it should modify "produce", but then how can the noun modifier "enough for generating...." jump over a verb modifier to modify the noun "energy"? Isn't there a rule saying that noun modifiers can only jump other noun modifiers?
There are no rules about what modifiers can and can't jump over. Some tendencies we see? Sure. But no ironclad rules. All we really care about is: 1) is the modifier logical? and 2) is the modifier reasonably close to what it's describing. If the answer to those questions is "yes" or even "I'm not sure," then you shouldn't treat the modifier as an error. Simple as that.

As for what "enough" is describing, I'd say it seems to be modifying "energy," but really, either interpretation is reasonable enough. Take another example:

    Tim ate enough food to obliterate the large intestine of a small mastodon.

Here, I'd say "enough" is describing the amount of "food," and so it's a noun modifier, but if you wanted to insist it was telling us how much he "ate," and is therefore a verb modifier, I'd see your point. It isn't worth losing sleep over. Either way, it seems logical, so I wouldn't treat it as an error.

Quote:
2) For choices B and C, why are the following constructions not parallel?

B: "enough... for electricity to be generated and to heat factories and homes."
C: "enough for generating electricity and to heat factories and homes."
The problem with (B) is more about meaning than faulty parallelism. Take another look:

Quote:
Scientists at the Los Alamos National Laboratory have succeeded for the first time in mining heat from the Earth’s interior and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat factories and homes.

First, the phrase "scale for electricity," makes me think there's a scale that measures electricity. That makes no sense. What would generating energy for this supposed scale have to do with heating factories?

Worse, if "to heat" is parallel to "to be generated," then we have the following meaning: The lab has produced enough energy for electricity to be generated efficiently and for electricity to heat factories and homes. Electricity might be consumed when the factories and homes are heated, but it's odd to claim that the electricity is doing the heating itself.

If I read it a few times, I can figure out what the author is trying to say, but the sentence is so muddy and confusing that it's clearly inferior to (D).

(C), on the other hand, is just faulty parallelism. "For generating" is a prepositional phrase and "to heat" is an infinitive verb phrase. That's no good.

Once you see the meaning issue in (B) and the faulty parallelism in (C), there's no reason to agonize any more. Those options are out.

I hope that helps!
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