Ask me anything about GMAT Sentence Correction and grammar Hello! I'm Charles Bibilos, GMAT Club's resident Verbal Expert, and a GMAT teacher and tutor since... nevermind, I'll feel old if I tell you. This thread is designed to be an absolute free-for-all on SC, and you're welcome to ask me absolutely anything. If your question is related to a specific question or a topic, please provide a link and a bit about what you want me to address. And if you're looking for very general advice on how to improve your SC skills, try these links first: Beginner's Guide to SC How to go from great (760) to incredible (780?!) on SC YouTube webinar: getting your priorities right on SC All of our live YouTube webinars by topic Our old Wednesday verbal chats, with transcripts Just be warned that non-official questions can be damaging on verbal, so I might be a bit dismissive of flawed, non-official questions. But still: it's an Ask Me Anything thread, so you're obviously welcome to ask me anything. Especially if it involves food. (Because I know you were going to ask: yes, caterpillars are indeed delicious when prepared properly. You're welcome.) (Edit: because there's a lot of randomness in my soul, I'll answer these questions in no particular order. I'll answer them all eventually, though!) And if you want to read some of the most generally useful posts on this thread, check out this greatest hits collection .

Hello GMATNinja , Below question is from Manhattan GMAT https://gmatclub.com/forum/the-universi ... 70345.html I was able to select correct answer for correct reasons. My doubt here is with sentence " like most libraries" . Shouldn't it be "like most other libraries" ?

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GMAT Ninja SC Expert - Ask Me Anything about GMAT SC and Grammar

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lemonmelon

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24 Jul 2020, 11:11

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lemonmelon

GMATNinja

Love your videos and keep them coming.

I came across this sentence in a RC passage (W.E.B. Du Bois, no surprise!), and though the meaning to me makes sense and it is easy on the ears, I am not entirely sure that I follow the parallel "structure", especially for the underlined part. I don't think I have come across a similar structure of: less/more + prep. phrase + than + clause

Sentence: "In 1903, however, Du Bois aligned himself with Trotter, Washington's militant opponent, less for ideological reasons than because Trotter had described to him Washington's efforts...."

Thanks in advance!

GMAT Ninja,
Can you please help me understand this comparison? I am having a hard time understanding what elements in this comparison are structurally parallel.

Any help is appreciated. Thanks!

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24 Jul 2020, 19:28

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lemonmelon

Good question! It's helpful to differentiate between what we rarely see in correct SC answers and what's definitively wrong. In the sentence you quoted, the comparison between a prepositional phrase and a clause isn't something we see very often, but it isn't WRONG either.

Practically speaking, if I saw that sentence in a GMAT question, I'd notice the unconventional comparison and maybe hesitate for a moment, but there's no way I'd eliminate the answer choice at that point.

The takeaway: Any time you see an option, and have the reaction you had -- "this seems logical and I can't pinpoint a definitive error" -- hold on to it. Look for more concrete issues first, and only return to the construction you were unsure about if you can't find anything else.

I hope that helps a bit!

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25 Jul 2020, 08:19

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GMATNinja,

I have question about this SC https://gmatclub.com/forum/in-small-dos ... 65369.html.

Quote:

In small doses, carbon monoxide can cause headaches, vertigo, nausea, and in larger doses, the victims can pass out and even die.
A. vertigo, nausea, and in larger doses, the victims can pass out and even die

B. vertigo, nausea, and the victims can pass out and even die in larger doses

C. vertigo, and nausea, and the victims can pass out and even die in larger doses

D. vertigo, and nausea; the victims can pass out and even die in larger doses

E. vertigo, and nausea; in larger doses, the victims can pass out and even die

I was able to get correct answer for correct reason e.g. list and place of modifier (in larger doses). My question is on words SMALL and LARGER. Isn't LARGE is comparative word for SMALL, and LARGER is comparative work for LARGE.

When first I read sentence I was hoping to see "LARGE" word in correct answer.

I am not able to understand SMALL vs LARGER comparison here. Shouldn't it be Small Vs Large.

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31 Jul 2020, 14:23

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Hello GMATNinja,

Below question is from Manhattan GMAT

https://gmatclub.com/forum/the-universi ... 70345.html

Quote:

The university science library, as most libraries, prohibits students to borrow rare, expensive, or popular reference materials; such materials are designated for use in the library only.

B. like most libraries, prohibits students from borrowing

I was able to select correct answer for correct reasons. My doubt here is with sentence " like most libraries". Shouldn't it be "like most other libraries" ?

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07 Aug 2020, 11:34

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sanchawla

When releasing an animal that has lived in captivity back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat.

A. releasing an animal that has lived in captivity back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat

B. an animal that has lived in captivity is released back into a wild environment, zoologists can never be sure if it will successfully adapt to its new habitat

C. releasing an animal back into a wild environment that has lived in captivity, zoologists can never be sure whether it will successfully adapt to its new habitat

D. an animal is released back into a wild environment that has lived in captivity, zoologists can never be sure if it will successfully adapt to its new habitat

E. an animal that has lived in captivity is released back into a wild environment, zoologists can never be sure whether it will successfully adapt to its new habitat or not

The answer is A but I marked E - is using ing form of verb with When appropriate? Why is E wrong?

First understand the difference between if and whether .
If is used for conditional statement
whether is used for optional statement

So , by this logic we can eliminate answer option B and D.
Remaining A,C,E
when we use whether, it is understood that animal will adapt or not .
'or not' at end of answer option E is causing redundacy.
Whether + or not is unidiomatic and redundant .
It was a close call between A and C but A is using correct grammatical structure so A is the answer.

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08 Aug 2020, 11:15

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Shubhp

sanchawla

Hey Shubhp,
Although I think the asker probably wanted some more clarity with option A, those are good points! The "or not" after "whether" is usually redundant, especially on GMAT sentences. The if/whether distinction also holds most of the time. So, there's not much wrong with the things you said. However (and this doesn't pertain to the question or a concept or grammar at all), posts on this particular topic "GMAT Ninja SC Expert - Ask Me Anything about GMAT SC and Grammar" are directed at GMATNinja

He's created this topic to answer questions from people who want an answer specifically from him. And there are many people like that.

I see that you've only recently joined gmatclub, so maybe you weren't aware of this.

I don't mean any harm. This is just to inform you, in case you didn't know.

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Updated on: 03 Sep 2020, 09:49

Originally posted by azfarsulaiman1 on 09 Aug 2020, 07:23.
Last edited by azfarsulaiman1 on 03 Sep 2020, 09:49, edited 1 time in total.

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Hi GMATNinja, would really like your help explaining here, very difficult to get it right. Special problem is in the OA since the first part has "whether it has been" tense form while the second has "whether Leonardo first sketched"

Official question here: https://gmatclub.com/forum/art-historia ... 76856.html

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15 Aug 2020, 19:31

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Hello!

I'm currently working on my Sentence Correction for GMAT. I'm do fairly well with the medium level questions but having some difficulty with the hard level. If I'm doing the questions timed, then I tend to get nervous and if the entire sentence or most of the sentence is underlined then just forget about it!! My nerves kick in and my focus goes out the door. Any tips you can share on how to tackle the 700 level SC questions and keeping nerves calm will be very helpful.

Looking forward to your response. Also, I hope my message is grammatically correct...

Regards,
Tahira

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15 Aug 2020, 23:27

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Hi Ninja,

may I know the difference between "which"and "of which"? I saw a question here and I think the first thing i need to know is the diff between these two...

Many successful startup companies have raised hundreds of millions of dollars, of which the majority must be repaid to investors and other preferred shareholders before employees receive any funds.

A) of which the majority must be repaid to investors and other preferred shareholders before employees receive any funds

B) of which the majority must be repaid to investors and other preferred shareholders before employees had received any funds

C) the majority of it must be repaid to investors and other preferred shareholders before employees receive any funds

D) and the majority of this must be repaid to investors and other preferred shareholders before the reception of any funds by employees

E) the majority of which are repaid to investors and other preferred shareholders before employees receive any funds

Thanks!

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16 Aug 2020, 03:14

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Hello GMAT Ninja,
Would you kindly give the explanation of this question from you ?

Canadian scientists have calculated that one human being should be struck every nine years by a meteorite, while each year sixteen buildings can be expected to sustain damage from such objects.

(A) one human being should be struck every nine years by a meteorite
(B) a human being should be struck by a meteorite once in every nine years
(C) a meteorite will strike one human being once in every nine years
(D) every nine years a human being will be struck by a meteorite
(E) every nine years a human being should be struck by a meteorite

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16 Aug 2020, 06:41

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Maghla

This question is discussed in detail here: https://gmatclub.com/forum/canadian-sci ... 01939.html BTW, that topic has GMAT Ninja reply.

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21 Aug 2020, 13:51

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GMATNinja

Please explain why option A &E is wrong
Manufacturers rate batteries in watt-hours; if they rate the watt-hour higher, the longer the battery can be expected to last.

A if they rate the watt-hour higher, the longer
B rating the watt-hour higher, it is that much longer
C the higher the watt-hour rating, the longer
D the higher the watt-hour rating, it is that much longer that
E when the watt-hour rating is higher, the longer it is

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22 Aug 2020, 08:24

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Unlike the nests of leaf cutters and most other ants, situated underground or in pieces of wood, raider ants make a portable nest by entwining their long legs to form "curtains" of ants that hang from logs or boulders, providing protection for the queen and the colony larvae and pupae.

(A) the nests of leaf cutters and most other ants,

(B) the nests of leaf cutters and most other ants, which are

(C) leaf cutters and most other ants, whose nests are

(D) leaf cutters and most other ants in having nests

(E) those of leaf cutters and most other ants with nests
Can you please explain how in option D in having modifies raider ants and why it's not modifying other ants.I thought that it's giving additional info for other ants.

How to look upon this whether at which entity in having is modifying.

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03 Sep 2020, 09:39

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Hi,

Could you please help me understand the difference between 'credit(ed) to' and 'credit(ed) with'. While solving SC questions with such idiomatic usage, I tend to select the wrong option.

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03 Sep 2020, 22:00

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GMATNinja San

I have the below observation in the following questions.
Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were last year.
(A) Heating-oil prices are expected to be higher this year than last because refiners are paying about $5 a barrel more for crude oil than they were
(B) Heating-oil prices are expected to rise higher this year over last because refiners pay about $5 a barrel for crude oil more than they did
(C) Expectations are for heating-oil prices to be higher this year than last year's because refiners are paying about $5 a barrel for crude oil more than they did
(D) It is the expectation that heating-oil prices will be higher this year over last because refiners are paying about $5 a barrel more for crude oil now than what they were
(E) It is expected that heating-oil prices will rise higher this year than last year's because refiners pay about $5 a barrel for crude oil more than they did
In C
Last years' is incorrect because we don't know last years' what can be Prices or Expectations (both logical so 2 possibilities)
Experts point out out that last years' or a valid apostrophe usage requires something to be in the possessive earlier as per my understanding of the thread.

However in the below:
We have option C correct with no possessive earlier. 2 possibilities are ape's Neanderthals (illogical) and ape's vocal tracts (logical). Only 1 logical
Neanderthals had a vocal tract that resembled those of the apes and so were probably without language, a shortcoming that may explain why they were supplanted by our own species.
(A) Neanderthals had a vocal tract that resembled those of the apes
(B) Neanderthals had a vocal tract resembling an ape’s
(C) The vocal tracts of Neanderthals resembled an ape’s
(D) The Neanderthal’s vocal tracts resembled the apes’
(E) The vocal tracts of the Neanderthals resembled those of the apes

Other issues aside in the above sentences,
Is the absence of an earlier possessive a deterministic grammar error or we have to resolve for meaning?

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09 Sep 2020, 15:27

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Dear GMATNinja
GMATNinjaTwo

I have a question regarding the usage of pronouns: "this" and "these"

As far as I know, they can be used as:

Demonstrative Adjectives:
e.g.
This book is amazing
These questions are really dumb

But why is always considered incorrect to use them as Demonstrative Pronouns?

eg. I agree to give them part of the territory because I think this is fair.

Some of the sources:

https://gmatclub.com/forum/sc-tips-tricks-275739.html: "This/that, these/those not followed by a noun = wrong."

https://gmatclub.com/forum/yerbamate202 ... l#p2553521: (guide from an user that scored 770) "Do NOT use this or these in place of nouns"

Best

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13 Sep 2020, 16:16

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GMATNinja GMATNinjaTwo

Another one!

Regarding this question:

Although many art patrons can readily differentiate a good debenture from an undesirable one, they are much less expert in distinguishing good paintings and poor ones, authentic art and fakes.

(A) much less expert in distinguishing good paintings and poor ones, authentic art and (INCORRECT)

(B) far less expert in distinguishing good paintings from poor ones, authentic art from (CORRECT)

What is this part "authentic art fromfakes" doing in the sentence? Is it an appositive? I thought there was a missing "and", so the right sentence would be something like this one:

....distinguishing good paintings from poor ones, and authentic art from fakes

Please let me know your comments.

Best

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14 Sep 2020, 04:52

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Dear GMATNinja GMATNinjaTwo

I have another question

Regarding this one:

The cathedrals of the Middle Ages were community centers just as much as they were purely religious edifices; and they were structures that represented a city’s commitment to a public realm, the opposite of being a private one.

(D) as much community centers as purely religious edifices, structures that represented a city’s commitment to a public realm, as opposed to a private one (CORRECT)

(E) as much community centers as they were purely religious edifices, structures representing a city’s commitment to a public realm, opposite of a private one (INCORRECT)

So, the OA is D) and the OE mentions in E) that " uses opposite of a private one to refer to a public realm, unreasonably suggesting that a public realm cannot coexist with a private realm"

So my question is, whats the difference between these two:

a public realm, as opposed to a private one
to a public realm, opposite of a private one

I am not able to see any difference between those two

Best

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14 Sep 2020, 19:12

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Quote:

Could you please take a look at this question?

https://gmatclub.com/forum/around-1900- ... l#p2520376

Q1. I have some question on the chronological sequence of the correct choice.

Around 1900, fishermen in the Chesapeake Bay area landed more than seventeen million pounds of shad in a single year, but by 1920, over-fishing and the proliferation of milldams and culverts that blocked shad from migrating up their spawning streams had reduced landings to less than four million pounds.

Does the underlined portions imply that: blocking (in simple past) appeared AFTER the reduction (past perfect)?

I think this sequence doesn't make sense at all.

You've probably heard that the past perfect is used for something that occurred in the past, BEFORE another action, event, or time marker occurred in the past. In evaluating this sentence, we need to see whether the use of past perfect is correct by attempting to find this secondary action/event/time marker in the past.

It's tempting to see the word "blocked" and think, "heck yes, there's my simple past time marker!" The problem is that not every -ed word is a verb (more -ed word fun can be found here). In this case, "blocked" is not actually a verb: it's an -ed modifier, and in this sentence is just modifying "milldams and culverts". So, "blocked" is not expressing an action/event/time marker in the past, and we don't have to evaluate whether it would work as the event AFTER our past perfect verb.

Instead, look elsewhere in the sentence to find this marker. You'll see that the clause begins with a time stamp, "by 1920." This is a perfectly acceptable time marker in the past, and in conjunction with our main verb ("had reduced"), the sentence tells us that the reduction happened before 1920. So, the past perfect works in this sentence.

Quote:

Q2. Why is choice A. wrong?
Why is present perfect tense wrong here?
Why is it illogical to say that blocking started in the past and remains in effect today?
"Milldams and culverts" are long-lasting infrastructure. So, IMO, it makes sense to say that the blocking is still relevant in the present context.

Remember, the main action of the clause, "had reduced," happened before 1920. "Blocked" is part of a phrase describing the thing responsible for this past reduction. So while there's no way to know if the milldams and culverts are still blocking fish, it's the blocking that occurred in the past that we care about.

Consider another example:

"Tim, who ruined Christmas by forgetting to buy presents for his children, was in the doghouse."
Could you argue that Tim is still ruining Christmas to this day? Sure. And knowing Tim, that's probably a safe assumption. (To say nothing of New Year's Eve and Valentine's Day and Saint Patrick's Day, etc.) But "was" is a past tense verb, so it makes sense to keep the act of ruining Christmas in the past tense, too.

I hope that helps!

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23 Sep 2020, 04:44

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Hi GMATNinja

I have a doubt about the below official question.

Desertification, a process in which the biological productivity of the land is sharply degraded by human abuse and natural phenomena, helped cause the famines that have killed hundreds of thousands in recent years.

(A) a process in which the biological productivity of the land is sharply degraded by human abuse and natural phenomena
(B) a process of the biological productivity of the land being sharply degraded by human abuse and natural phenomena
(C) a process of human abuse and natural phenomena that sharply degrade the biological productivity of the land
(D) which is the process of human abuse and natural phenomena sharply degrading the land's biological productivity
(E) which is the process of human abuse and natural phenomena that sharply degrade the land's biological productivity

C. of human abuse and natural phenomena that sharply degrade
D. which is the process of human abuse and natural phenomena sharply degrading
E. which is the process of human abuse and natural phenomena that sharply degrade

In options C,E does the modifier (that sharply degrade) refer to both human abuse and natural phenomena, or just the touching noun - natural phenomena

Q1: In case of a compound noun, does the modifier modifies both the nouns or only the preceding noun.?

Q2: In option D -- Does sharply degrading modifies the compound noun or just the preceding noun.? As per my understanding, verb+ing without a preceding comma modifier the noun it touches. Please correct me if I am wrong