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Sub 505 Level|   Parallelism|   Verb Tense/Form|                     
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Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Travelers to mars would have to 'endure', ' avoid', 'contend' and 'ward'

Only C fits in.
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Travelers to Mars would to have to
- endure
-avoid
-contend
-(perhaps even) ward


Answer C - The elements are parallel here
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Parallelism:
endure X, avoid Y, contend Z, and perhaps ward off T
Only C is correct.

Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward ==> CORRECT
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Hope it's clear.

i am a vietnamese too. I am happy to see a chief of designer here in this forum. I am still in vietnam. nice to meet you
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Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.

Issue: Parallelism

Analysis: This is a straightforward parallelism question that requires all the verbs in the sentence to be in infinitive forms (since two non-underlined actions are already in infinitive form)

I have highlighted the issues in option below

(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Answer: (C)
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The problem with this sentence is mainly with Parallelism.
This sentence provides a "list of things". i.e. — to endure , ( to ) avoid , ( to ) contend , ( to ) ward off must be parallel.
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Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

meaning:
mars traveller are subjected to a,b,c,d

grammar:
parallelism: a,b,c,d should be all parallel

ans = c
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(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding
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Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

ans- Only C maintains the parallelism in the list. (endure /avoid /contend /ward off)
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This question tests parallelism. Once we understand what the items are in the list, we need to make sure that these items are parallel with each other. By that, we mean that the items should all be the same part of speech/form etc.

How do we understand what is the right form?

We use the non-underlined part of the sentence to figure out what parallelism the other items exhibit. Then we make sure that all of them follow the same parallelism.

The sentence says that ‘Travelers to Mars … have to endureavoid

So, it only makes sense for the other verbs to be ‘contend’ and ‘ward’

Now let’s scan the options vertically and eliminate the other options:

(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Eliminate Option A, B, D, and E.

Option C is the best option.

Hope this helps!
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Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

In option E) Contending and warding seems parallel. Also why do we have to make the whole list(the non underlined part) paralllel. Why is option E incorrect please explain
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I agree that the words ‘contending’ and ‘warding’ in option E are parallel, and that is exactly what the examiner wants - to confuse test-takers.
Now let's answer your question first – “Why does the whole list have to be parallel?” Please remember that the aim of sentence correction is to ensure that 'the overall meaning of the sentence' is logically correct. Let’s look at what the sentence is telling us.
The sentence tells us about different things ‘travelers to Mars’ would have to do. The list of things they have to do starts with “endure…..”. The other things they have to do are ‘avoid…., contend….and ward…’. Now, as per logic, and so as to avoid any confusion, all the items of the same motive should be in the same form. Now, in option E, although the two actions 'contending & warding' are parallel wrt each other, they are not parallel with the other 2 items related to 'travelers to Mars'. Hence, option E is incorrect.
Therefore, as per the explanation given by the CrackVerbal expert, 'the various items in a list must all be in the same form' is a very important point to keep in mind when one encounters such GMAT questions.
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OE:
Parallelism; Grammatical construction
This sentence provides a list of three conditions Mars travelers would
certainly have to contend with, along with one additional thing they
might have to do—ward off contamination by Martian life-forms. The
items in the list are most clearly and effectively structured in parallel—as
phrases beginning with infinitive verb forms—to endure, (to) avoid, (to)
contend, (to) ward off. Because the sentence introduces all these actions
as something travelers would have to do, repeating the hav[ing] to
construction in the final item of the list is redundant.
A. The phrase having to is not parallel with the other items in the list,
and it unnecessarily repeats the sense of the introductory phrase,
which identifies all items in the list as things travelers would have
to do.
B. The verb form warding is not parallel with the other items in the
list.
C. Correct. The sentence uses proper grammar and parallel
construction.
D. The participial form contending violates the parallel structure of the
list of infinitive phrases. The reader is misled into thinking that
contending with chemically reactive Martian soil describes what
travelers would have to do to avoid radiation doses.
E. The participial phrases contending with and warding off violate the
parallel structure established by the list of infinitive phrases.
The correct answer is C
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Quote:
Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Hello Experts,
ParamjitDasGMAT sayantanc2k

What is the meaning conveyed by WOULD HAVE TO ENDURE ?

What is the tense of the verb (Present Tense / Past tense ? )

Thanks
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PriyamRathor
Quote:
Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Hello Experts,
ParamjitDasGMAT sayantanc2k

What is the meaning conveyed by WOULD HAVE TO ENDURE ?

What is the tense of the verb (Present Tense / Past tense ? )

Thanks

It's a hypothetical modal verb -- a 'modal' verb is formed by adding a modal such as will/can/could/may/might/should/would etc. to either the base form or the "have" + participle form of the verb, depending on the tense. Examples of such constructions would include "would go/have gone, could run/have run, etc".

The difference between the base and participle forms, in the case of "would", is to do with whether we want to express an idea in the 2nd-order subjunctive (open hypothetical), for which we use "would have to endure", or the 3rd-order subjunctive (past or closed hypothetical) conditional, for which we would use "would have endured".

Do also note that the infinitive "to endure" is a function of the verb "have" rather than the conditional syntax.
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ParamjitDasGMAT
PriyamRathor
Quote:
Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Hello Experts,
ParamjitDasGMAT sayantanc2k

What is the meaning conveyed by WOULD HAVE TO ENDURE ?

What is the tense of the verb (Present Tense / Past tense ? )

Thanks

It's a hypothetical modal verb -- a 'modal' verb is formed by adding a modal such as will/can/could/may/might/should/would etc. to either the base form or the "have" + participle form of the verb, depending on the tense. Examples of such constructions would include "would go/have gone, could run/have run, etc".

The difference between the base and participle forms, in the case of "would", is to do with whether we want to express an idea in the 2nd-order subjunctive (open hypothetical), for which we use "would have to endure", or the 3rd-order subjunctive (past or closed hypothetical) conditional, for which we would use "would have endured".

Do also note that the infinitive "to endure" is a function of the verb "have" rather than the conditional syntax.

Thank you ! ParamjitDasGMAT


So can I conclude that in the below OG question in the correct answer choice B would have been spent is 3rd -order subjunctice conditional ?

Thanks.


Quote:
New data from United States Forest Service ecologists show that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, it saves seven dollars that would not be spent on having to extinguish big fires.

(A) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, it saves seven dollars that would not be spent on having to extinguish

(B) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, seven dollars are saved that would have been spent on extinguishing

(C) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel saves seven dollars on not having to extinguish

(D) for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, that it saves seven dollars on not having to extinguish

(E) for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, that seven dollars are saved that would not have been spent on extinguishing

LINK- https://gmatclub.com/forum/new-data-from-united-states-forest-service-ecologists-show-102295.html
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Thank you ! ParamjitDasGMAT


So can I conclude that in the below OG question in the correct answer choice B would have been spent is 3rd -order subjunctice conditional ?

Thanks.


Quote:
New data from United States Forest Service ecologists show that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, it saves seven dollars that would not be spent on having to extinguish big fires.

(A) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, it saves seven dollars that would not be spent on having to extinguish

(B) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, seven dollars are saved that would have been spent on extinguishing

(C) that for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel saves seven dollars on not having to extinguish

(D) for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, that it saves seven dollars on not having to extinguish

(E) for every dollar spent on controlled small-scale burning, forest thinning, and the training of fire-management personnel, that seven dollars are saved that would not have been spent on extinguishing

LINK- https://gmatclub.com/forum/new-data-from-united-states-forest-service-ecologists-show-102295.html[/quote]

This would be a correct interpretation.
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Dear Friends,

Here is a detailed explanation to this question-
WaterFlowsUp
Travelers to Mars would have to endure low levels of gravity for long periods of time, avoid large doses of radiation, contend with the chemically reactive Martian soil, and perhaps even having to ward off contamination by Martian life-forms.


(A) contend with the chemically reactive Martian soil, and perhaps even having to ward
(B) contend with the chemically reactive Martian soil, and perhaps even warding
(C) contend with the chemically reactive Martian soil, and perhaps even ward
(D) contending with the chemically reactive Martian soil, and perhaps even to ward
(E) contending with the chemically reactive Martian soil, and perhaps even warding

Concepts tested here: Verb Forms + Parallelism

• "would + base form of verb ("have" in this case)" is a correct construction for referring to a hypothetical future action.
• "to + base form of verb" is the correct infinitive verb form.

A:
1/ Option A incorrectly uses the construction "would + present participle ("verb + ing" - "having" in this sentence)" to refer to the hypothetical future action of warding off contamination; remember, "would + base form of verb ("have" in this case)" is a correct construction for referring to a hypothetical future action.

B:
1/ Option B fails to maintain the infinitive verb form construction ("to + base form of verb"), as it uses the present participle ("verb+ing" - "warding" in this case) in place of the base form of verb; remember, "to + base form of verb" is the correct infinitive verb form.

C: Correct.
1/ This answer choice maintains the correct infinitive verb form ("to + base form of verb" - "contend" and "ward" in this sentence).
2/ Option C correctly uses the construction "would + have" to refer to the hypothetical future action of warding off contamination.

D:
1/ Option D fails to maintain the infinitive verb form construction ("to + base form of verb"), as it uses the present participle ("verb+ing" - "contending" in this case) in place of the base form of verb; remember, "to + base form of verb" is the correct infinitive verb form.

E:
1/ Option E fails to maintain the infinitive verb form construction ("to + base form of verb"), as it uses the present participle ("verb+ing" - "contending" and "warding" in this case) in place of the base form of verb; remember, "to + base form of verb" is the correct infinitive verb form.

Hence, C is the best answer choice.

All the best!
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