Question: Science Project Challenges

Comment on Science Project Challenges

Hi. I too got the answer choice E on my own. However, i used a different logic. Since the part begins with "By", it is a dependent clause. Hence, the part after comma has to be an independent clause. Option D does not make a clause. Hence omitted.
gmat-admin's picture

In answer choice D, the part after the comma is still a clause. We have a subject (challenges) and a verb (confronted).


Could you explain in another way why had confronted is in the past perfect and completed in the simple past. Could I reverse it, for exemple "... had completed the project, they confronted many logistical challenges." explaning, after completed, they confronted many logistical challenges.
gmat-admin's picture

The sentence structure "By the time X, Y had occurred" tells is that Past Event Y happened BEFORE Past Event X

Two examples:

By the time his guests arrived, Joe had eaten all of the cake.

By the time it stopped raining, Joe had stopped crying.

Dear Brent, how if the answer D says this : "many logistical challenges had been confronted by them"? Should be 100% correct right?
gmat-admin's picture

Yes, that would be technically okay. However, that's a passive sentence, and passive sentences are seldom the best answer choices on the GMAT.

Hi Brent, is there any SlideShare file or something similar that has consolidated summary of major points covered in the videos, like you had for quants? It is difficult to go back to videos to revise the concepts.
gmat-admin's picture

Sorry about I don't have a similar resource for Reading Comprehension.
That said, I feel that there are many positive aspects I was reviewing and summarizing your notes. That process is one of the best ways to reinforce your learning.


Is "By the time" a prepositional phrase?
gmat-admin's picture

On its own, "by the time" isn't a prepositional phrase, since it isn't modifying any nouns or verbs.

Compare that to the sentence "Joe watered the roses BY the pool."
In this case, "BY the pool" is a prepositional phrase that tells us more about the ROSES. (Which roses? The ones BY the pool.)

Here's another example: Joe completed the work BY Friday.
In this case, "BY Friday" is a prepositional phrase that modifies COMPLETED. (When did Joe complete the work? BY Friday.)

That said, "BY the time the scientists had completed the project" is a dependent clause that provides a timeframe for WHEN the scientists CONFRONTED the challenges

Does that help?

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