The voluminous personal papers of Thomas Alva Edison reveal that his

Dear Friends,

Here is a detailed explanation to this question-

Concepts tested here: Tenses + Parallelism + Awkwardness/Redundancy

• Semicolons and the “comma + conjunction” construction are used to link two independent clauses; commas are used to link an independent clause with a dependent one; comma cannot be used to join two independent clauses.
• The simple past tense is used to refer to events that concluded in the past.
• 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".

A: This answer choice fails to maintain parallelism between "in a flash of inspiration" and "evolved slowly from previous works"; please remember, any elements linked by a conjunction ("but" in this sentence) must be parallel.

B: This answer choice fails to maintain parallelism between "in a flash of inspiration" and "were slowly evolved from previous works"; please remember, any elements linked by a conjunction ("but" in this sentence) must be parallel. Further, Option B uses the passive voice construction "were slowly evolved", rendering it awkward and needlessly wordy.

C: Correct. This answer choice maintains parallelism between "spring to life in a flash of inspiration" and evolved slowly from previous works". Further, Option C correctly uses the simple past tense verb "evolved" to refer ot an event that concluded in the past. Additionally, Option C is free of any awkwardness or redundancy.

D: This answer choice incorrectly uses the past perfect tense verb "had evolved" to refer to an event that concluded in the past; please remember, the simple past tense is used to refer to events that concluded in the past, and 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".

E: This answer choice incorrectly uses conjunction ("but" in this sentence) to join the independent clauses "his inventions did not spring to life in a flash of inspiration" and "they were slowly evolved from previous works"; please remember, semicolons and the “comma + conjunction” construction are used to link two independent clauses. Further, Option E uses the passive voice construction "they were slowly evolved", rendering it awkward and needlessly wordy.

Hence, C is the best answer choice.

To understand the concept of "Simple Tenses" on GMAT, you may want to watch the following video (~1 minute):



To understand the concept of "Past Perfect Tense" on GMAT, you may want to watch the following video (~1 minute):



All the best!
Experts' Global Team

d)did not spring to life in a flash of inspiration but had slowly evolved

what is wrong with option d

In D, the use of past perfect 'had evolved' to describe the nature of a phenomenon is erroneous. The springing and evolving are concurrent happenings and so there is no need to sequence them as one before the other. That is why D loses

(C) did not spring to life in a flash of inspiration but evolved slowly

Notice that "did" appears before "spring". Hence we cannot write "sprang" because we cannot write two past tenses in same sentence. Note that "did not spring" = "sprang" which is parallel to past tense "evolved". The structure of the sentence is such that "spring" and "evolved" cannot be identically parallel. But both the verb tenses are in simple past tense. And that is why they are parallel.

Hence, it is not always necessary that all the entities in a list must be identically parallel. They should be made identically parallel only when it is possible to do so. In an e-gmat course concept namely Parallelism - Helpful Tips, we discuss how far entities can be parallel in the list.

Hope this helps.

Thanks.

Shraddha

(E) did not spring to life in a flash of inspiration but were slowly evolved

Use of the passive construction, 'were slowly evolved' invalidates this answer choice.

Hi Chris,
You mention the above as the reason why E is wrong.
So, Do we need the voices ( passive/active ) to be parallel in a x but y structure?

Regards,
Sach

Hi Sachin,

In the construction “not X but Y”, X and Y should be parallel, but it is not necessary for the voices to be the same if the context demands so. For example:

The beggars did not get any money but were helped in other ways.

In this sentence, “did not get” is in active voice but “were helped” is in passive. It is so because here both the entities cannot be identically parallel. If we make both the voice active, the meaning will be violated.

However, this is not the case with the OG question. Choice E reads:

E) did not spring to life in a flash of inspiration but were slowly evolved

In this choice we can make both the entities identically parallel without violating the meaning of the sentence. We can easily say:

Did not spring to life in a flash of inspiration but slowly evolved…

The takeaway is that we must keep the entities as parallel as possible. When we can have identically parallel entities to convey the intended logical meaning, we must keep them that way. The list can be made non-identical only if the logical meaning cannot be conveyed by making the entities absolutely parallel.

Hope this helps.
Thanks.
Shraddha

I'm no help on your question 2, but I will respond to your first question about 'did'.

This is a great meaning question around the difference between "sprang to life not in a flash" and "did not spring to life in a flash". The intent of the sentence is to show that Edison's inventions were not the result of a flash of inspiration but rather were the result of an evolutionary process. By saying his inventions "sprang to life not in a flash of inspiration but evolved slowly" you are actually setting up a contradictory statement because you are saying his inventions sprang to life through evolution, but evolution is slow and certainly does not "spring to life". By changing the statement to read "his inventions did not spring to life but evolved slowly" you get the proper meaning that this was not a quick, 'spinging' action but rather a slow evolutionary process.

Does that help?

KW

You mention that you picked A because verbs were in past tense and parallel. For one thing, tense does not need to be same between various parts of the sentence. For example:

Buddha has studied hard for GMAT and will surely score well on GMAT.

This is a valid sentence, though the tenses are not same (first part uses present perfect and second part uses simple future).

Nevertheless, even going by your thought process, you mention that both verbs are parallel. I am assuming you mean that sprang and evolved are parallel in A. So, let us dissect the sentence at these verbs:

The voluminous personal papers of Thomas Alva Edison reveal that his inventions typically:

(a) sprang to life not in a flash of inspiration
BUT
(b) evolved slowly from previous works.

So, the mini-sentences we have here are:

(a) The voluminous personal papers of Thomas Alva Edison reveal that his inventions typically sprang to life not in a flash of inspiration
(b) The voluminous personal papers of Thomas Alva Edison reveal that his inventions typically evolved slowly from previous works.

Hopefully you see the issue with (a). We would not say:

He prepared for GMAT not with a hope of scoring 650.

We would rather say:

He did not prepare for GMAT with a hope of scoring 650.

Hey Kyle
Can you please explain why option E is wrong.

Hi,

I see that there is still some confusion regarding this choice. Shraddha has done a good analysis of the errors in choice E in her post here:https://gmatclub.com/forum/the-voluminous-personal-papers-of-thomas-alva-edison-reveal-81030-20.html#p1148384

However, to solidify your understanding of the intended meaning of the author and the errors in various choices for this question, please refer to our detailed video solution of this question here:
https://e-gmat.com/blogs/?cat=45&paged=11



Regards,
Neeti.

Can any one explain why ansewr choice 'D' is incorrect ??? I was confused between C & D . Anyway chose D.

D is incorrect because it uses "had", which is unnecessary.

As per the meaning of the sentence, it says Papers revealed that his inventions evolved slowly rather than in a flash of inspiration.

So, We don't need any "had" here. Also, spring in a flash and evolved slowly should be in the same tense form. But in D, it is not so.

Correct... the past perfect tense ("had evolved") cannot be used because we do not have two past actions occurring at different times.

Hi, I understand that there is a need for parallelism but I do not understand how some inventions can 'evolve slowly' by themselves? I thought evolve is like animals evolving but inventions are not creatures, they need to be created and improved on by someone else? Am I misunderstanding something?

Thanks!

@Ywp

'Evolve' simply means to transform for better either by itself or by somebody's effort. So many inanimate things evolve. For example, we say the volcanoes have evolved slowly over time. However, did anyone evolve them? They evolved by themselves.

How do inventions evolve by themselves? When the field is ripe with a lot of designs, the prior inventions open up a ready synergy for many inventors to create more and unique devices. That is the reason that we have so many new inventions springing up especially in scientific fields. This subtle momentum is the evolution of inventions.

Is the construction " not sprang to life in a flash of inspiration but evolved slowly" correct?

Here, if the stem A was like the above statement "not sprang... but evolved", would that be correct usage?

Generally, we're much better off evaluating official options than creating our own constructions, but for what it's worth, I can't think of any scenario in which "not sprang" would work.

You could write, "Tim's shriveled moribund body sprang to life," and you could write "Tim's shriveled moribund body did not spring to life." But "Tim's shriveled moribund body not sprang?" Nah.

But again, it's not worth devoting much brain space to this.

I hope that helps a bit!