The study, called the National Lung Screening Trial, focused

Question

The study, called the National Lung Screening Trial, focused on a specific high‐risk  group: 53,000 current and former heavy smokers, aging from 55 to 74, which had smoked for at least 30 pack‐years .

A. group: 53,000 current and former heavy smokers, aging from 55 to 74, which had smoked for at least 30 pack‐years
B. group: 53,000 current and former heavy smokers, aged 55 to 74, that had smoked for at least 30 pack‐years
C. group: 53,000 current and former heavy smokers, aged 55 to 74, who smoked for at least 30 pack‐years
D. group: 53,000 current and former heavy smokers, aged 55 to 74, who had smoked for at least 30 pack‐years
E. group: 53,000 current and former heavy smokers, who were aged 55 to 74, and who had smoked for higher than at least 30 pack‐years

mikemcgarry · Accepted Answer

Hi, there. I'm happy to help.

First of all, here's a blog article you may find helpful: https://magoosh.com/gmat/2012/that-vs-which-on-the-gmat/ As for this question, important GMAT idea #1 is --- don't use that/which for human beings; use "who" for human beings. That eliminates (A) and (B) right away. Answer (E) is wordy and redundant ---- we'll tube that one also. That leaves (C) & (D), which are remarkably similar. In fact the only difference is the verb tense: (C) ...smoked... (D) ... had smoked... The first is simple past tense, and the second is past perfect. The past perfect is used to indicate that this verb's action took place before some other event in the past. Here, the main verb of the sentence "focused" is in the past. The question is --- did the smoking and the focusing happen at the same time, or was the smoking clearly before the focusing? Well, by the time the study was created and they focused on folks, those folks already had been smoking for quite some time. The smoking clearly has to happen before the focusing. This necessitates the past perfect structure. That's why (D) is correct and (C) is not. Answer = D Does this make sense? Let me know if you have any more questions. Mike

dvinoth86 · Answer

Who should be placed close to smokers right?
it is not followign the touch rule!! 
please clear my doubt

mikemcgarry · Answer

Dear dvinoth86 Here's what I am going to say. I don't know the source of this question. Not all GMAT prep questions are created equal. The SC questions that appears on the GMAT itself are gems, absolutely superb in their clarity and polish, and some test prep sources produce SC questions of comparably high quality. Other GMAT prep sources, to be honest, produce junk SC. Let's say, I have my suspicions about this question. This is not a question that would appear on the real GMAT. Here's the sentence with the least offensive answer, (D): The study, called the National Lung Screening Trial, focused on a specific high‐risk group: 53,000 current and former heavy smokers, aged 55 to 74, who had smoked for at least 30 pack‐years. Yes, you are correct --- the modifier touch rule requires the modifier ("who had smoked ...") to touch the noun it modifies ("smokers"). This sentence does not do that, and so is less than ideal. Is it out-and-out incorrect? That's a matter of debate. A vital modifier can intervene between a modifier and its target. See this post for more on that idea: https://magoosh.com/gmat/2012/gmat-gramm ... modifiers/ Here, the intervening phrase "aged 55 to 74" is clearly not vital. It is set off by commas, which is the hallmark of a non-vital modifier. No clear rule justifies its position between the noun and the modifier. At the same time, it's very short, and putting it there involves absolutely no ambiguity --- that's not a resounding vote of support, but some folks would argue on that basis that it's correct. Admittedly, there is not universal consensus on the grammar of this particular point. One further piece of support is that --- any attempt to reword the sentence to eliminate this problem makes the sentence longer and more awkward. For example: The study, called the National Lung Screening Trial, focused on a specific high‐risk group: 53,000 current and former heavy smokers, who were aged 55 to 74 and had smoked for at least 30 pack‐years. Hardly a model sentence. There is no good way to rework (D) as it stands, which is another sorta argument in its favor. Mathematics this ain't!!! I'm sorry I can't give you a more definitive answer. On the real GMAT, correct answers will be 100% correct (though not necessary ideal), and incorrect answers will be wrong. On this question, the best answer is in a gray zone ---- not something you will encounter on the real GMAT. Moral : don't accord the same degree of trust in each and every practice question you see. Some practice questions sources are of much higher quality, and others don't hold up the standard. If you want some high quality questions, follow the link in the signature of the post. Let me know if you have any further questions. Mike :-)

tuanquang269 · Answer

There are only two potential candidate for the correct choice are choice C and choice D.

In the non-underlined part, the study focused (simple past). So the subjects of the studies must "had smoked", smoking before the study progress.

So, choice D is the correct one.

ashish8814 · Answer

hi  mike mcgarry..
i was confused btw option c & d. as it is obvious about time period. we are talking about people who smoked for at least 30 years. there is no confusion in sequence of events if we use simple past tense. plz clarify.

sairam595 · Answer

Dear  mike

D. group: 53,000 current and former heavy smokers, aged 55 to 74, who had smoked for at least 30 pack‐years

to use past perfect tense we need two related events, one is earlier event in the past & the other later event

Please explain how to determine later event in option D - whether it is "focused" or "aged"

mikemcgarry · Answer

Dear mike D. group: 53,000 current and former heavy smokers, aged 55 to 74, who had smoked for at least 30 pack‐years to use past perfect tense we need two related events, one is earlier event in the past & the other later event Please explain how to determine later event in option D - whether it is "focused" or "aged" Dear ashish8814 & smartguy595 , I'm happy to respond. :-)

The most important thing to remember is that this is NOT a high quality practice question. You both are asking for clarification as if understanding this question more deeply will help you. This is fundamentally a misapprehension. You do not necessarily enhance your understanding by wrestling with low quality SC questions. In the gigantic underlined section, the only difference between (C) & (D) is the verb tense. The GMAT might test verb tenses if all that is underlined is the verb itself, but if the GMAT underlines a long section such as this, it is unlikely to have two choices that differ only in verb tense. That's too picayune a split. Incidentally, smartguy595 , in this sentence, " focused " is a full verb, a verb in the past tense. The word " aged " is purely a participle, a noun-modifier, not a full verb. It's very important to recognize the difference between participles and full verbs. The truth is that this is not a particularly clean split. I think (D) sounds more natural, but one could certainly make a valid argument for (C). This is one of the ways that this question is not high quality. On a high quality question, one choice is correct and the other four are clearly wrong. On this question, (D) is correct and (C) is arguably correct also. Don't stress over this, thinking one must be absolutely right and one must be absolutely wrong. The question simply is not that good. Here's a high quality SC question: Balancing the need for Does all this make sense? Mike :-)

vishalkumar4mba · Answer

Sorry for a silly question...

can you please help me in understanding the verb here for the subject "The Study" ???

mikemcgarry · Answer

Dear vishalkumar4mba , I'm happy to help! :-)

My friend, that is NOT a stupid question. :-)

Kudos to you for humbly asking for the help you need! This is what all students should do! There are always at least some ways in life that we are all learning, and humility is one of the powerful attitudes both for getting the help we need and assimilating the information we get! Probably by asking this question, you have helped someone else who was afraid to ask. Good for you! The verb of " the study " is the past tense verb " focused ." This is always a tricky thing about the past tense form of regular verbs--the "-ed" form: it can act as either a straight ordinary verb or as a past participle. In college, I studied Physics . = used as a full verb, the main verb of the sentence The Egyptian hieroglyphics, studied for centuries with no success, finally were deciphered by Champollion in the 1820's . = used as past participle, a noun-modifier Here's the whole sentence from this problem: The study = subject called the National Lung Screening Trial = noun modifier, modifies the subject focused = main verb focused on = idiom a specific high‐risk group = object of preposition " on " The semicolon is used here for clarification: it adds clarification & explanation to what is meant by " high-risk group ." 53,000 current and former heavy smokers = an appositive phrase , identical to " high-risk group ." aging from 55 to 74 = present participle, noun modifier #1, modifying " smokers " which had smoked for at least 30 pack‐years = relative clause, noun modifier #2; the mistake is that we shouldn't use the relative pronoun " which " to refer to people--we should use " who ." Does all this make sense? Mike :-)

RMD007 · Answer

Hi,

I was confused between C and D but selected C.In your explanation, you have compared events "focused" and "smoked" with respect to their time frames and thus the use of past perfect is proper according to you.

I have two queries.
1. In my thought, we can use past perfect tense for earlier event and simple past tense for later event only if the events are RELATED to each other. Here smoking of people has not resulted in focusing of study. So use of past perfect tense makes sense here?

2. What if we had another choice mentioning 
....had been smoking...
is this choice correct?

mikemcgarry · Answer

Dear RMD007 , I'm happy to respond. :-)

First of all, I am not sure where you picked up that rule that for the past & past perfect tense rules work " only if the events are RELATED to each other ." It would be 100% grammatically correct, but illogical, to say: Abraham Lincoln had died by the time I voted in my first US presidential election . The illogicality of that sentence has nothing to do with the tenses, which are perfectly correct: it's illogical because there is essentially no reason to discuss those two events in the same sentence. As long as two events appear in the same sentence on the GMAT, they are related enough. I would be highly suspicious of any source that promulgated a rule such as that. Furthermore, the events in this sentence are strongly related: the researchers would not have conducted the study on those people if they hadn't been smoking for years! Of course the past perfect is fine here. There is absolutely no reason to introduce the progressive tense . 1) ... current and former heavy smokers, who had smoked for at least 30 pack‐years . = a plain factual statement 2) ... current and former heavy smokers, who had been smoking for at least 30 pack‐years . = awkward Version #2, with the past perfect progressive, changes the meaning by emphasizing the performance of the action. This sounds awkward in a strange way, as if we are emphasizing something that is not relevant to the context. Does all this make sense? Mike :-)

AR15J · Answer

Thanks Mike for the wonderful explanation, but RMD001's question made me remind of the rule I learned in e-gmat course.

Incorrect usage of past perfect:

use past perfect only to express the sequencing of two related events

Recently scientists learned about the changes in the earth that had happened during the last ice age-- marked incorrect

The reason why above two events are incorrect-- because these are two unrelated events.

Please guide on the above example.

mikemcgarry · Answer

Dear AR15J , I'm happy to respond. :-)

I don't know whether the way you are reporting this rule is the way that it was taught, but as you are reporting it here, I would say that this rule does not accord with my own understanding of grammar and doesn't seem as if it would be particularly helpful on the GMAT SC. Among other things, if any two events are discussed in the same sentence, they must be related in some way! In my understanding, the deciding factor is redundancy--whether the time sequence is already made clear by other elements of the sentence. For example, in this sentence, the past perfect is not needed: Recently scientists learned about the changes in the earth that happened during the last ice age . The word " recently " indicates the order of events, as does the phrase " during the last ice age ." You don't need to have a technical understanding of exactly when the ice ages were, but it's good to have the rough idea that the last one took place before humans started doing this thing we call "civilization." In other words, it was a long time ago! By contrast, consider this sentence: Bohr's model of the atom made clear the origin of spectral lines, an atomic feature that J. J. Thompson's plum-pudding model of the atom had been unable to explain . Are the two events related? It's unclear what the relation is, if you don't know outside information about the history of atomic physics. The past perfect is necessary in this sentence because the use of this tense is the only grammatical feature in the sentence that lets us know that Thompson did his work before Bohr . I don't think the question "are the two events related?" is a particularly useful question for determining anything about the sentence. Does all this make sense? Mike :-)

AR15J · Answer

Thanks Mike for the wonderful explanation.

If we changed the above sentence --

Scientists learned about the changes in the earth that had happened during the last ice age.

The above sentence is correct while the below one is incorrect. Correct me if I am wrong.

Scientists learned about the changes in the earth that happened during the last ice age.

mikemcgarry · Answer

Dear AR15J , I'm happy to respond. :-)

Let's be clear. In the previous example and this example, I wouldn't call the the first version, with the past perfect tense, 100% wrong. It's definitely not preferred. It definitely has problems and would be unlikely to be correct on the GMAT, but it's not "wrong" the way a SVA error is 100% wrong. The second version is definitely better. The grammar in this sentence is up to the standards of a correct OA on a GMAT SC question. Scientists learned about the changes in the earth that happened during the last ice age . The reason that the past perfect tense is not needed is because, once again, we know that the " last ice age " was a really really long time ago. That knowledge frames the time-relationship of the events, so the past perfect is not needed to clarify that. Does all this make sense? Mike :-)

jatin093 · Answer

Shouldn't the answer be C as the smoked and focused are unrelated events?

ReedArnoldMPREP · Answer

Why do you think correct answer 'd' makes 'focused' and 'smoked' related events?

My reason for D over C is that the past tense 'smoked' makes it unclear if the study followed them as they smoked 30 pack-years, whereas the meaning is quite clearly that they wanted tos study smokers who already HAD SMOKED 30 pack-years.

The study, called the National Lung Screening Trial, focused on a specific high‐risk  group: 53,000 current and former heavy smokers, aging from 55 to 74, which had smoked for at least 30 pack‐years

A. group: 53,000 current and former heavy smokers, aging from 55 to 74, which had smoked for at least 30 pack‐years
B. group: 53,000 current and former heavy smokers, aged 55 to 74, that had smoked for at least 30 pack‐years
C. group: 53,000 current and former heavy smokers, aged 55 to 74, who smoked for at least 30 pack‐years
D. group: 53,000 current and former heavy smokers, aged 55 to 74, who had smoked for at least 30 pack‐years
E. group: 53,000 current and former heavy smokers, who were aged 55 to 74, and who had smoked for higher than at least 30 pack‐years

ExpertsGlobal5 · Answer

Hello  jatin093 ,

We hope this finds you well.

Having gone through the question and your query, we believe we can resolve your doubts.

D is better than C because it correctly uses the past perfect tense verb "had smoked" to refer to the earlier of two actions that concluded in the past - the smokers smoking for at least 30 pack‐years and the study focusing on a particular high-risk group.

Whether the two events are related is immaterial; the past perfect tense (marked by the use of helping verb "had") is used when a sentence contains two actions in the past; the helping verb "had" is used with the action in the "greater past".

We hope this helps. 
All the best!
Experts' Global Team

VerbalBot · Answer

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The study, called the National Lung Screening Trial, focused

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The study, called the National Lung Screening Trial, focused

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