The majority of scientists believe that to reduce

[davetzulin]

The majority of scientists believe that to reduce and stabilize atmospheric concentrations of carbon dioxide, emissions must be cut at the source by fossil fuels that are burned more efficiently and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether.

(A) fossil fuels that are burned more efficiently and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether
(B) fossil fuels that are burned more efficiently and, in some cases, those that are replaced altogether with alternatives such as hydrogen fuel cells
(C) burning fossil fuels more efficiently and, in some cases, by replacing fossil fuels altogether with alternatives such as hydrogen fuel cells
(D) more efficiency in the burning of fossil fuels and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether
(E) the more efficient burning of fossil fuels and, in some cases, by fossil fuels that are replaced altogether with alternatives such as hydrogen fuel cells





OA = C

This was in a recent Thursdays with Ron on -ing. I have a question about what Ron mentioned in regards to parallelism for A,D

(A) fossil fuels that are burned more efficiently and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether

ignoring the more obvious error where "emissions are cut by fossil fuels"

Ron mentioned that "fossil fuels" and "alternatives such as hydrogen fuel cells" are not parallel. I agree that the meaning is not parallel since one is a raw source of energy whereas the other is more like a battery (hydrogen is the raw source). Is this a different type of parallelism than what is described in the guide? I did not think we had to go beyond parts of speech with parallelism.


(D) more efficiency in the burning of fossil fuels and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether

same here, "efficiency" is a noun, and alternatives is a noun.

so this below is not parallel?

i like the feel of the wind, apples, and oranges

[jnelson0612]

Excellent question, Dave. Yes, the rule is that the elements in question must not only be structurally parallel (for example, the same or comparable parts of speech) but also logically parallel (the elements are similar or can reasonably be compared).

[tapdoan_hp]

C says that emission must be cut... by burning fossil fuels more efficiently...
Does C imply that emission burn the fossil fuels?
I remember Ron said that in the structure: S + V1 by V2-ing: S is the subect of the action V-ing
PLease correct me!

[tim]

first --
OFFICIALLY CORRECT ANSWERS ARE CORRECT!
do not question officially correct answers!
far too many students on this forum make the mistake of questioning the correct answers; please note that doing so is a complete waste of your time and effort. i.e., exactly 0% of the time that you spend posting "isn't this official answer wrong?" is productive, and exactly 100% of that time is wasted.

"is this correct?" is never a productive question to ask about one of GMAC's correct answers. the answer is always yes.
"is this wrong?" / "is this X type of error?" is never a productive question to ask about one of GMAC's correct answers. the answer is always no.

instead, the questions you should be asking about correct official answers, if you don't understand them, are:
"why is this correct?"
"how does this work?"
"what understanding am i lacking that i need to understand this choice?"

this is a small, but hugely significant, change to your way of thinking.
you will suddenly find it much easier to understand the format, style, and conventions of the official problems if you retire the idea that they might be wrong.

as for your question, where did Ron say what you attributed to him?

[mcmebk]

C says that emission must be cut... by burning fossil fuels more efficiently...
Does C imply that emission burn the fossil fuels?
I remember Ron said that in the structure: S + V1 by V2-ing: S is the subect of the action V-ing
PLease correct me!

Hi Ron, I am having the same trouble to understand this question:

in this post: the-chicago-and-calumet-rivers-originally-flowed-into-the-t3836.html

You explained that ""BY ___ING" retains the subject of the preceding clause, 'by constructing' seems to refer back to the rivers as its ostensible subject, implying (absurdly) that the rivers themselves constructed the canals."

The situation in this question is exactly the same, why is it ok here?

Thanks.

[mcmebk]

C says that emission must be cut... by burning fossil fuels more efficiently...
Does C imply that emission burn the fossil fuels?
I remember Ron said that in the structure: S + V1 by V2-ing: S is the subect of the action V-ing
PLease correct me!

Hi Ron I also have same doubts about this question.

In this question: the-chicago-and-calumet-rivers-originally-flowed-into-the-t3836.html you said that "'by constructing' seems to refer back to the rivers as its ostensible subject, implying (absurdly) that the rivers themselves constructed the canals.", wouldn't it be the same here in C?

Thank you in advance.

[RonPurewal]

In this question: the-chicago-and-calumet-rivers-originally-flowed-into-the-t3836.html you said that "'by constructing' seems to refer back to the rivers as its ostensible subject, implying (absurdly) that the rivers themselves constructed the canals.", wouldn't it be the same here in C?

Thank you in advance.

you have a point -- i agree that this problem isn't perfect. but, if you want to argue against one answer choice, you need to argue in favor of another answer choice, too.

this is really, really important. simply put, remember that one of the five choices has to be ... the correct answer choice.
so, sure, your objection is noted -- but which choice did you think was less problematic?

in this problem, i don't love the use of "by ___ing" there, either. but, fortunately, none of the other choices use that modifier in an ideally perfect way, either.
so, this is one of those "oh well..." moments. you shrug your shoulders, say "meh", and then move on to the next split.
... which is the parallelism.

(by the way, when parallelism is an issue, it should ALWAYS be the first thing that you consider.)

[thanghnvn]

I will try to explain the use of "burning" in the oa C. Ron teach us to learn from the oa.

there is no relevant explantion of the use of doing in general grammar books. we have to learn/infer the new point from the official answer of gmat. I infer the following

in some cases, there is no action noun (there is no burnation), and to talk to a general action, we have no choice but use of "doing". When "doing" is used to refer to general action, it dose not need a subject. "doing" used this way is similar to an action noun.

when there is an action noun (attempt, for example) , gmat encourage us to use the action noun rather than "doing". there is many sc problems test this points. But the use of the action noun is preference not compulsory and the use of "doing" to talk of general action when the action noun exists is not absolutely wrong.

some grammar books said that "doing" as a general noun can not take direct object. This mean we have to use "doing+of+object", not "doing +object". But this point is not important/relevant on gmat land.

attempt to learn gmat is good

"attempt" here refers to a general action.

burning (of) the fuel more efficiently is good for us

"burning" here refers to a general action.

in contrast, "doing" can be a participle, which is used to refer to a specific action of a specific subject. "doing" used this way needs its subject. its subject must appear somewhere in a logic place in the sentence. "doing" in this use is explained much in general grammar books.

That is why sometimes "doing" needs a subject and sometimes dose not. the official answer C in this sc problem shows that "doing" there is used as general noun

That is all I think. There is no formal explanation in general grammar book about this point.

[jlucero]

I will try to explain the use of "burning" in the oa C. Ron teach us to learn from the oa.

there is no relevant explantion of the use of doing in general grammar books. we have to learn/infer the new point from the official answer of gmat. I infer the following

in some cases, there is no action noun (there is no burnation), and to talk to a general action, we have no choice but use of "doing". When "doing" is used to refer to general action, it dose not need a subject. "doing" used this way is similar to an action noun.

when there is an action noun (attempt, for example) , gmat encourage us to use the action noun rather than "doing". there is many sc problems test this points. But the use of the action noun is preference not compulsory and the use of "doing" to talk of general action when the action noun exists is not absolutely wrong.

some grammar books said that "doing" as a general noun can not take direct object. This mean we have to use "doing+of+object", not "doing +object". But this point is not important/relevant on gmat land.

attempt to learn gmat is good

"attempt" here refers to a general action.

burning (of) the fuel more efficiently is good for us

"burning" here refers to a general action.

in contrast, "doing" can be a participle, which is used to refer to a specific action of a specific subject. "doing" used this way needs its subject. its subject must appear somewhere in a logic place in the sentence. "doing" in this use is explained much in general grammar books.

That is why sometimes "doing" needs a subject and sometimes dose not. the official answer C in this sc problem shows that "doing" there is used as general noun

That is all I think. There is no formal explanation in general grammar book about this point.

I'm not sure if there's a specific question here, but I'll just emphasize one point you made- "burning" can function in many ways, so to make a clear, unambiguous sentence, the GMAT will use language like "the burning" in order to qualify that this is a gerund/noun and avoid the ambiguity of some of the other options.

[eggpain24]

In this question: the-chicago-and-calumet-rivers-originally-flowed-into-the-t3836.html you said that "'by constructing' seems to refer back to the rivers as its ostensible subject, implying (absurdly) that the rivers themselves constructed the canals.", wouldn't it be the same here in C?

Thank you in advance.

you have a point -- i agree that this problem isn't perfect. but, if you want to argue against one answer choice, you need to argue in favor of another answer choice, too.

this is really, really important. simply put, remember that one of the five choices has to be ... the correct answer choice.
so, sure, your objection is noted -- but which choice did you think was less problematic?

in this problem, i don't love the use of "by ___ing" there, either. but, fortunately, none of the other choices use that modifier in an ideally perfect way, either.
so, this is one of those "oh well..." moments. you shrug your shoulders, say "meh", and then move on to the next split.
... which is the parallelism.

(by the way, when parallelism is an issue, it should ALWAYS be the first thing that you consider.)

yeap！parallelism always wins！（sometimes GMAT breaks it own preferred rule, but other wrong choices are fatally wrong to force you to pick up the less awful choice!)

[tim]

Hooray for parallelism!

[RonPurewal]

sometimes GMAT breaks it own preferred rule,

This is the wrong interpretation.

The correct interpretation is, "The GMAT doesn't test 'preferences'." Because it doesn't.

With the exception of idioms (of which only the most basic / most ubiquitous are tested these days), everything tested in GMAT SC has an objective basis in mechanics/grammar, context/meaning, or both.
"Preference" is not a thing. If you invent it, you're removing a great deal of simplicity, and replacing it with completely unnecessary complexity.

[eggpain24]

sometimes GMAT breaks it own preferred rule,

This is the wrong interpretation.

The correct interpretation is, "The GMAT doesn't test 'preferences'." Because it doesn't.

With the exception of idioms (of which only the most basic / most ubiquitous are tested these days), everything tested in GMAT SC has an objective basis in mechanics/grammar, context/meaning, or both.
"Preference" is not a thing. If you invent it, you're removing a great deal of simplicity, and replacing it with completely unnecessary complexity.

surely agree

I think I might not get my words well organized in the previous post= = ... but really understand what you mean!

[tim]

Glad to hear it!

[RonPurewal]

More generally, if it appears that a "rule" is being "broken" in some problem, you should think very carefully about whether the context is different.

ALL grammatical elements are affected by intended meaning. In fact, grammar doesn't even exist without an intended meaning.

So, in the case of perceived inconsistencies, consider whether there are relevant differences in context.