Source = GMATPrep test #1

Industrialization and modtern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.

a. while at the same time they have introduced some 100,000 dangerous chemical pollutants, having
b. while at the same time introducing some 100,000 dangerous chemical pollutants that have
c. while they have introduced 100,000 dangerous chemical pollutants at the same time, and have
d. but introducing some 100,000 dangerous chemical pollutants at the same time that have
e. but at the same time introduce some 100,000 dangerous chemical pollutants, having

hi, I'm having a very difficult time with this problem, I'm not sure why B would be the correct answer, pls help, thanks!

I chose A because I thought "indstrialization and modtern....have improved" and "they have introduced" are parallel, and the last setence "having gone virtually..." is a modifier.

Chester, you GMAT logic (looking for parallel construction) is sound, but you fell into a GMAT trap by relying solely on the definitive parallelism of answer choice A. Just becaue "have introduced" seems better than "introducing," we cannot conclude that the latter is provably incorrect. The real issue with this question is the modifier. The sentence is attempting to indicated that the chemical pollutants have gone unregulated since they were developed, a sentiment indicated clearly and correctly in answer choice B.

In answer choice (A) the modifier having does not clearly describe the pollutants. In fact, when the sentence is rewritten, having seems to most closely describe they, the subject of the clause (They, having gone virtually unregulated....., have introduced some 100,000 dangerous chemical pollutants).

Hope that helps!
-dan

Thanks for your help Dan!

- So have improved....and...improving is grammatically correct, right?

- Thanks for pointing out it's a modifier issue.

when I first looked at the question, "...gone virtually unregulated since they were developed more than 50 years ago. "

I thought the "they" was referring to the subjects of the setence, Industrialization and modern methods. (Actually can "they" refer to Industralization and modtern mtehods"?) But either way, looks like I need to pay more attention to clarify of meaning.

Thanks Dan!

Chester,

Have improved and introducing is okay in this usage. Additionally, the pronoun they does refer to the compound subject industrialization and modern methods of insect control . The problem is the lack of clarity with the referent for the modifier having.

Keep those questions coming!
-dan

Thanks Dan! Now I'm clear on that one.

I have couple SC questions on the same test that I had questions with, thanks for your help!


the investigations of many psychologists and anthropologists support the generalization of there being little that is a significant difference in the underlying mental porcesses manifested by people from different cultures

a.same as above
b.of there being little that is significantly different
c.of little that is significantly different
d.that there is little that is significantly different
e.that there is little of significant differences

I eliminated the first 3 choices since I think "that" is needed after support the generalization.
I chose E because I didn't see any major error/issue with it.


The Nobel prize in chemistry was awarded to three scientists for their discovery that plastic can be made electrically conducitve - an advance that has led to imporvements in film, television screens, and windows.

a.same as above
b.that plastic can be made electrically conductive - this advance leading
c.that plastic can be made to be eletrically conductive, and this advance led
d.of plastic's ability to be made electrically conductive, with this advance leading
e.of plastic being able to be made electrically conductive - an advance that has led

I'm down to between A and C for this problem, since I think the latter part of the sentence needs a verb, correct?

But what is wrong with C ?

Hi Chester,

On the first question in your last post ("The investigations of many psychologists...") you are correct that the idiom is "generalization that." The problem with E is the mismatch between "little" (used for uncountable things) and "differences" (countable things). I think that in order to use "significant differences," you would have had to word it "there are few significant differences." Come to think of it, that re-write reveals another mismatch between the singular "is" and the plural "differences."

On the second question in your last post ("The Nobel prize in chemistry...") there are three differences between A and C. One is the easier split to deal with: A says "that plastic can be made electrically conductive" while C says "that plastic can be made to be electrically conductive." At the very least, the "to be" is not necessary: they mean the same thing. At the very worst, the extra "to be" could imply a different meaning: consider the similar examples "the man was born rich" (rich at birth) vs. "the man was born to be rich" (destined to become rich).

The second difference is more subtle: the dash vs. an "and." Consider the core of the sentence (the core = the subject, verb and object with all of the modifiers ignored or put in parentheses) and you have "The Nobel prize was awarded." The modifiers "in chemistry" (what kind of prize), "to three scientists" (to whom it was awarded), "for their discovery" (why it was awarded), and "that plastic can be made..." (what type of discovery) just provide extra information. Choice A uses the dash: "- an advance that has led to improvements..." correctly indicating that the "discovery" was the "advance." In contrast, choice C uses "and" to extend the core of the sentence so that it reads "The Nobel prize was awarded...and this advance led to improvements...." illogically referring to the Nobel prize itself as this advance.

Finally, there is a verb difference between A and C: "has led to improvements" or "led to improvements." The present perfect "has led" indicates that the improvements started in the past and are still occuring - the intended meaning.

Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.

What is in side the two[b]s is the main clause or the most important idea - Industrialization and modern methods of insect control have improved the standard of living around the globe

the rest are subordinate or secondary ideas or subordiante clauses so we need a suordinating marker ." while " can be used to express contrast between ideas and its also a subordinate marker( subordinate conjunctuion)

what has gone unregulated for the past 50yrs ? > dangerous chemical pollutants .in the original " having gone........" suggests that Industrialization and mordern methods have gone unregulated - this is not what the writer wants to say so A is out .
D,E are out because Dand E use but ( a coordinating conjunction)

c is out because C uses ,and ( cordinating conjunction)

This leaves only B

B is coorect because 1.0 uses "while " a subordinating conjunction - to express the minor idea
2.0 uses that clause ( restrictive) to refer back to chemical pollutants

I am still doubtful about the intent of the author: Does he want to say that the pollutants were unregulated or the modern methods were unregulated. I understood the sentence like this: modern methods were developed 50 years ago. They have been unregulated since then. Hence they have introduced 100,000 pollutants. Apparently my reasoning is wrong. Was there any clue in the sentence to find out that the author wanted to say that the pollutants were unregulated?

I frequently make mistakes in finding out the intent of the author. How do you all gurus catch the intent? :)

Thanks.

this is a good point; on my first reading of this sentence, i likewise associated the adjective 'unregulated' with the industrial procedures themselves, not the chemicals thereby produced.

however, the gmat hero comes to the res-Q with the following fact:
you won't have to decide the author's intent.

you see, here's how it works: if an ambiguous or unclear sentence con be resolved in more than one way, then CHOOSING THE OPTIONS WITH CORRECT GRAMMAR, USAGE, ETC. WILL OBVIATE THE NEED to decide between the two versions.

remember the order of the 3 'c's in the hierarchy of sentence correction: 1, correctness; 2, clarity; 3, concision.
these are in order.
DO NOT think about clarity / semantic meaning before you resolve the issues that are grammatically right vs. wrong.
if you follow these steps in the correct order, you won't have to decide between two or more legitimate meanings, although you still might have to
* eliminate absurd meanings, or
* choose choices that uphold the meaning of an unambiguous original sentence over altered versions.

at risk of being terribly redundant, though, one more time for the road: if the original doesn't make the author's intent clear, and the answer choices display alternative meanings (both of which are reasonable), then the issue should resolve itself when you eliminate the choices that are just plain wrong from a linguistic standpoint.