Verbal Review 18 : Kudzu, an Asian vine

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Verbal Review 18 : Kudzu, an Asian vine

by NandishSS » Thu Oct 26, 2017 2:33 am
Kudzu, an Asian vine that has grown rampantly in the southern United States since introducing it in the 1920s to thwart soil erosion, has overrun many houses and countless acres of roadside.

(A) that has grown rampantly in the southern United States since introducing it in the 1920s to thwart
(B) that has grown rampantly in the southern United States, since it was introduced in the 1920s for thwarting
(C) that has grown rampant in the southern United States since it was introduced in the 1920s to thwart
(D) growing rampant in the southern United States since introducing it in the 1920s for thwarting
(E) growing rampantly in the southern United States, since it was introduced in the 1920s to thwart

OA: C

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Verbal Review 18 : Kudzu, an Asian vine

by GMATGuruNY » Thu Oct 26, 2017 3:53 am
NandishSS wrote:Kudzu, an Asian vine that has grown rampantly in the southern United States since introducing it in the 1920s to thwart soil erosion, has overrun many houses and countless acres of roadside.

(A) that has grown rampantly in the southern United States since introducing it in the 1920s to thwart
(B) that has grown rampantly in the southern United States, since it was introduced in the 1920s for thwarting
(C) that has grown rampant in the southern United States since it was introduced in the 1920s to thwart
(D) growing rampant in the southern United States since introducing it in the 1920s for thwarting
(E) growing rampantly in the southern United States, since it was introduced in the 1920s to thwart
A: Kudzu...has grown...since introducing it
D: Kudzu...growing...since introducing it
In these options, Kudzu seems to be both the agent of introducing and the referent for it, implying that KUDZU IS INTRODUCING KUDZU.
This meaning is nonsensical.
Eliminate A and D.

Generally, for + VERBING cannot serve to express intent.
B: it was introduced...for thwarting soil erosion
Here, for thwarting incorrectly serves to express the intent of whoever introduced Kudzu.
To express this intent, we use to + VERB, as in the OA:
it was introduced TO THWART soil erosion.
Eliminate B.

One purpose of the present perfect -- has/have + VERBed -- is to express an action that STARTED IN THE PAST AND CONTINUES IN THE PRESENT.
E: growing...since...the 1920s
Here, the modifier in red implies that the act of growing started in the past and continues in the present.
For this reason, this action must be expressed as a present perfect verb:
Kudzu...HAS GROWN...since...the 1920s
Eliminate E.

The correct answer is C.

rampant is an ADJECTIVE that means uncontrolled.
rampantly is an ADVERB that means in an uncontrolled way.
In the SC above, both seem acceptable.

Correct: Kudzu has grown rampant.
Here, rampant is an ADJECTIVE serving to modify Kudzu.
The conveyed meaning is that -- as a result of the action in blue -- Kudzu is now UNCONTROLLED.

Correct: Kudzu has grown rampantly.
Here, rampantly is an ADVERB serving to modify has grown.
The conveyed meaning is that Kudzu has grown IN AN UNCONTROLLED MANNER.
Last edited by GMATGuruNY on Fri Aug 09, 2019 6:41 pm, edited 2 times in total.
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by NandishSS » Thu Oct 26, 2017 4:13 am
HI Mitch,

Is it not Kudzu, act of growing started in the past and continues still in the present.

Is the act still in progress(present)?

Where am I going wrong?

Thanks
Nandish

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Kudzu

by GMATGuruNY » Thu Oct 26, 2017 4:40 am
NandishSS wrote:HI Mitch,

Is it not Kudzu, act of growing started in the past and continues still in the present.

Is the act still in progress(present)?

Where am I going wrong?

Thanks
Nandish
Generally, a VERBing modifier expresses an action that is CONTEMPORANEOUS with an actual verb.
If the actual verb happens in the past, so does the VERBing action.
E: growing...was introduced
Here, the usage of growing (VERBing modifier) seems to imply that the act of growing was CONTEMPORANEOUS with the actual verb in blue.
Since was introduced happens in the past, so should the act of growing.
Since the intended meaning is that the act of growing continues in the present, eliminate E.
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by sagarock » Wed Nov 08, 2017 6:06 pm
gmat guru,i understand why introducing is incorrect in sentence,but why these two sentences are correct?
1) The best way to extract the flavor from saffron threads is to soak them in liquid after pounding them
2)The tablet must not be taken before getting up in the morning.
And,are there more questions in og that test this concept?

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by GMATGuruNY » Thu Nov 09, 2017 5:59 am
sagarock wrote:gmat guru,i understand why introducing is incorrect in sentence,but why these two sentences are correct?
1) The best way to extract the flavor from saffron threads is to soak them in liquid after pounding them
2)The tablet must not be taken before getting up in the morning.
And,are there more questions in og that test this concept?
The best way to extract the flavor from saffron threads is to soak them in liquid after pounding them.
Here, the action in blue lacks an explicit agent.
As a result, the following is implied:
The best way [for a person] to extract the flavor from saffron threads is to soak them in liquid after pounding them.
The implication is that the implied PERSON in brackets is performing all three actions (to extract, to soak, pounding).
Thus, the act of POUNDING has a clear and logical agent: the implied person in brackets.

SC11 in the OG12 is similar:
There are several ways [for a person] to build solid walls using just mud or clay, but the most extensively used method has been to form the mud or clay into bricks, and, after some preliminary air drying or sun drying, to lay them in the wall in mud mortar.
Here, all of the actions in blue are performed by the implied person in brackets.
Thus, the act of DRYING has a clear and logical agent: the implied person in brackets.
2)The tablet must not be taken before getting up in the morning.
Here, the main action -- must not be taken -- has an explicit agent: the tablet.
As a result, the TABLET seems also to be the agent of getting, implying that the TABLET is GETTING up in the morning -- clearly not the intended meaning.
For this reason, the sentence above would be considered incorrect on the GMAT.
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by oneniceshoot » Mon Nov 13, 2017 5:28 am
GMATGuruNY wrote:
for + VERBING is an ADJECTIVE.
It must serve to modify a NOUN.
It cannot serve to modify a VERB.
B: was introduced...for thwarting
Here, for thwarting (adjective) cannot serve to modify was introduced (verb).
Eliminate B.

Thanks for your detailed answers.

You have mentioned that for + VERBING is an ADJECTIVE.It must serve to modify a NOUN.

Would you please give any explanation or example about this principle? I am really confused about it. Thanks so much for your time!

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by parry » Sun May 13, 2018 3:00 am
Hi, Mitch,

Your explanations really help. I clearly understand why other choices are wrong here.

However, I have a doubt regarding option C.

In this part that has grown rampant in the southern United States since it was introduced in the 1920s to thwart , doesn't it was introduced begs for the question who introduced?
it was introduced (by whom?). the agent is never mentioned in this sentence.

Thanks.

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by GMATGuruNY » Sun May 13, 2018 3:22 am
oneniceshoot wrote:
GMATGuruNY wrote:
for + VERBING is an ADJECTIVE.
It must serve to modify a NOUN.
It cannot serve to modify a VERB.
B: was introduced...for thwarting
Here, for thwarting (adjective) cannot serve to modify was introduced (verb).
Eliminate B.

Thanks for your detailed answers.

You have mentioned that for + VERBING is an ADJECTIVE.It must serve to modify a NOUN.

Would you please give any explanation or example about this principle? I am really confused about it. Thanks so much for your time!
SC11 in the OG11:
New genetic evidence provides compelling support for classifying Africa's forest elephants and its savanna elephants as separate species.
Here, for classifying is an adjective serving to describe support.
Question: What KIND of support?
Answer: support FOR CLASSIFYING.
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by GMATGuruNY » Sun May 13, 2018 4:01 am
parry wrote:Hi, Mitch,

Your explanations really help. I clearly understand why other choices are wrong here.

However, I have a doubt regarding option C.

In this part that has grown rampant in the southern United States since it was introduced in the 1920s to thwart , doesn't it was introduced begs for the question who introduced?
it was introduced (by whom?). the agent is never mentioned in this sentence.

Thanks.
Generally, the usage of a passive verb implies one or both of the following:
1. The agent of the passive action is unknown.
2. The agent of the passive action is unimportant to the meaning of the sentence.
The SC above is concerned primarily with the rampant GROWTH of Kudzu.
To understand this meaning, a reader does not need to know who or what introduced this Asian vine in the 1920s.
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by parry » Sun May 13, 2018 4:50 am
Thank you very much. :)


GMATGuruNY wrote:
parry wrote:Hi, Mitch,

Your explanations really help. I clearly understand why other choices are wrong here.

However, I have a doubt regarding option C.

In this part that has grown rampant in the southern United States since it was introduced in the 1920s to thwart , doesn't it was introduced begs for the question who introduced?
it was introduced (by whom?). the agent is never mentioned in this sentence.

Thanks.
Generally, the usage of a passive verb implies one or both of the following:
1. The agent of the passive action is unknown.
2. The agent of the passive action is unimportant to the meaning of the sentence.
The SC above is concerned primarily with the rampant GROWTH of Kudzu.
To understand this meaning, a reader does not need to know who or what introduced this Asian vine in the 1920s.

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by Mo2men » Fri Mar 08, 2019 5:58 am
GMATGuruNY wrote:
NandishSS wrote:Kudzu, an Asian vine that has grown rampantly in the southern United States since introducing it in the 1920s to thwart soil erosion, has overrun many houses and countless acres of roadside.

(A) that has grown rampantly in the southern United States since introducing it in the 1920s to thwart
(B) that has grown rampantly in the southern United States, since it was introduced in the 1920s for thwarting
(C) that has grown rampant in the southern United States since it was introduced in the 1920s to thwart
(D) growing rampant in the southern United States since introducing it in the 1920s for thwarting
(E) growing rampantly in the southern United States, since it was introduced in the 1920s to thwart
A: Kudzu...has grown...since introducing it
D: Kudzu...growing...since introducing it
In these options, Kudzu seems to be both the agent of introducing and the referent for it, implying that KUDZU IS INTRODUCING KUDZU.
This meaning is nonsensical.
Eliminate A and D.

Generally, for + VERBING cannot serve to express intent.
B: it was introduced...for thwarting soil erosion
Here, for thwarting incorrectly serves to express the intent of whoever introduced Kudzu.
To express this intent, we use to + VERB, as in the OA:
it was introduced TO THWART soil erosion.
Eliminate B.

One purpose of the present perfect -- has/have + VERBed -- is to express an action that STARTED IN THE PAST AND CONTINUES IN THE PRESENT.
E: growing...since...the 1920s
Here, the modifier in red implies that the act of growing started in the past and continues in the present.
For this reason, this action must be expressed as a present perfect verb:
Kudzu...HAS GROWN...since...the 1920s
Eliminate E.

The correct answer is C.

rampant is an ADJECTIVE that means uncontrolled.
rampantly is an ADVERB that means in an controlled way.
In the SC above, both seem acceptable.

Correct: Kudzu has grown rampant.
Here, rampant is an ADJECTIVE serving to modify Kudzu.
The conveyed meaning is that -- as a result of the action in blue -- Kudzu is now UNCONTROLLED.

Correct: Kudzu has grown rampantly.
Here, rampantly is an ADVERB serving to modify has grown.
The conveyed meaning is that Kudzu has grown IN AN UNCONTROLLED MANNER.
Hi GMATGuru,

In choice B, does the 'comma' before 'since' change the meaning?

Thanks

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by GMATGuruNY » Sat Mar 09, 2019 4:14 am
Mo2men wrote:Hi GMATGuru,

In choice B, does the 'comma' before 'since' change the meaning?

Thanks
Generally, COMMA + SINCE after a clause serves to express a CAUSAL relationship.
An OA in GMATPrep:
Prospecting for gold was a relatively easy task, since erosion put gold literally within reach of anybody with a pan.
Here, the clause in blue serves to express what CAUSED prospecting to be a relatively easy task.

B: An asian vine...has grown rampantly in the southern United States, since it was introduced in the 1920s.
Here, the usage of COMMA + SINCE seems to imply that the red clause CAUSED the vine to grow.
Not the intended meaning.
Eliminate B.

The intention here is to express a TEMPORAL relationship -- specifically, to convey WHEN the vine started grow.
For this meaning to be conveyed, the comma before since should be omitted, as in the OA:
An ancient vine...has grown rampant in the southern United States since it was introduced in the 1920s.
Here, the portion in blue conveys WHEN the vine began to grow rampant.
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by vietnam47 » Fri Aug 09, 2019 6:21 pm
NandishSS wrote:Kudzu, an Asian vine that has grown rampantly in the southern United States since introducing it in the 1920s to thwart soil erosion, has overrun many houses and countless acres of roadside.

(A) that has grown rampantly in the southern United States since introducing it in the 1920s to thwart
(B) that has grown rampantly in the southern United States, since it was introduced in the 1920s for thwarting
(C) that has grown rampant in the southern United States since it was introduced in the 1920s to thwart
(D) growing rampant in the southern United States since introducing it in the 1920s for thwarting
(E) growing rampantly in the southern United States, since it was introduced in the 1920s to thwart

OA: C
we do not need to know about "grow rampant/rampantly" to solve this. "comma since" in E is definitely wrong because I will think that this phrase modify the "has overun".
middle modifier/phrase can cause ambiguity.