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03 Jul 2021, 20:47
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C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
22% (01:49) correct
78%
(01:58)
wrong
based on 402
sessions
History
Date
Time
Result
Not Attempted Yet
Fifty years ago, ecologists studying wolf recolonization down from Canada into Washington State hypothesized that by killing coyotes, wolves will reverse the mesopredator overpopulation occurring when wolves were eliminated from this region nearly a century earlier.
A) by killing coyotes, wolves will reverse the mesopredator overpopulation occurring when wolves were
B) by killing coyotes, wolves would reverse the mesopredator overpopulation that occurred when wolves were
C) by killing coyotes, wolves would reverse the mesopredator overpopulation that had occurred when wolves had been
D) wolves, by killing coyotes, will reverse the mesopredator overpopulation that had occurred when wolves were
E) wolves would, by killing coyotes, reverse the mesopredator overpopulation that occurred when wolves had been
THIS TOPIC IS TEMPORARILY LOCKED
03 Jul 2021, 20:50
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OFFICIAL EXPLANATION
THE PROMPT
The easiest way to make that fact about both prior events clear is to use past perfect for both.
→ Because the first part of the sentence is in the simple past tense, the correct word to refer to the future (in the past) is would and not will.
THE OPTIONS
→ The phrase wolves were should be wolves had been: the wolf elimination took place before the hypothesis, which is the latest event in time and is described by the simple past tense.
→ The word occurring should probably be that had occurred.
As this option stands, it erroneously intimates that the overpopulation [was continuously] occurring when wolves were eliminated [not continuous].
ELIMINATE A
→ If you are not sure, keep B and compare to C (after you eliminate the last two).
ELIMINATE B
→ This sentence correctly uses would to refer to a future event in the past.
→ It also uses the past perfect tense to describe the two earlier events.
KEEP
→ The phrase wolves were should be wolves had been because this wolf elimination took place before the hypothesis.
→ Bizarre verb tenses for the timeline.
In this option, the earliest event is written in simple past tense whereas the second-in-time event (mesopredator overpopulation) is written in past perfect!
ELIMINATE D
→ The style is a bit strange. True, short phrases such as by killing coyotes can be placed between auxililary (would) and main verb (reverse). But the other options do not "stick" this phrase in the middle of the verb construction.
ELIMINATE E
The best answer is C.
Another strategy
Split #1: would is correct but will is not
Eliminate options A and D for using will.
When we talk about the "future in the past," we use X would happen.
Split #2: Compare the timelines of B, C, and E.
Choose the option whose verbs are designed to convey the timeline—not that just happen to do so if you can keep track of the time markers.
Option B:
A) wolves were eliminated a century before the ecologists hypothesized = wolves were eliminated 150 years ago
B) mesopredator overpopulation occurred = at some point in time . . . close to when wolves were eliminated?
C) ecologists hypothesized = 50 years ago
→ This option does not look terrible, but it seems odd that event B gets simple past tense because mesopredator overpopulation occurred after 150 years ago but before 50 years ago.
In other words, the mesopredator overpopulation comes before the hypothesis set down 50 years ago.
How do we best signal this pre-hypothesis timing of the mesopredator overpopulation?
We use had occurred to make it clear that overpopulation preceded the scientists' hypothesis.
After we think about this sentence for awhile, that fact seems obvious, but upon first reading, tracking on the timeline is hard. Make it easy.
Option C:
A) wolves had been eliminated a century earlier = wolves had been eliminated 150 years ago, before the mesopredator overpopulation and before the hypothesis
B) mesopredator overpopulation had occurred at some time in the past after the wolves had been eliminated but before the ecologists hypothesized
C) ecologists hypothesized 50 years ago
→ This option seems better than B.
Past perfect verb tense is used to describe "past of the past" events such as A and B here, both of which occurred before the hypothesis.
Can past perfect be used for two or more events in the past of the past that did not occur at the same time? Of course!
The immigrant children were exhausted because they had traveled for weeks, been without enough food or water, and not slept for nearly two days.
Option E:
A) wolves had been eliminated= sometime before the hypothesis and before the mesopredator overpopulation
B) mesopredator overpopulation occurred = when? contemporaneously with the scientists hypothesis? No.
Mesopredator overpopulation is in the past of the past.
C) ecologists hypothesized
Compare these three.
Which one uses the verbs most efficiently or in a way that is most true to their purpose?
Option E is the worst of the lot because it contains a mixed or garbled message: two past of the past events, but one is described by one tense and the other, by another tense.
Eliminate E.
Now, Option B or C?
Err on the side of clarity.
Using past perfect tense with sequence words is okay when the sequence words are not terribly clear and the sentence is dense.
Pick option C.
NOTES
• Sequence of events
A) 150 years ago: wolves were eliminated from Washington State
Sometime after #1 but BEFORE 50 years ago:
B) the population of mesopredators, including coyotes, grew too large
C) 50 years ago: ecologists were studying (contemplating) wolf recolonization.
The ecologists explored the idea of moving wolves from Canada down to Washington State
→ notice: "ecologists [WHO WERE] studying [the possibility of] wolf recolonization"
D) 50 years ago: ecologists hypothesized that bringing wolves from Canada to Washington state would reverse the problem of mesopredator overpopulation.
The ecologists hypothesized that this reversal would occur because wolves would kill coyotes. Apparently, coyotes constituted many or maybe all of the mesopredators whose population had grown too much.
Events C and D happened pretty much simultaneously. Both events are described in the nonunderlined portion of the sentence.
Ecologists studying is a reduced relative clause.
Relative clause: ecologists who were studying [the possibility of] wolf recolonization
Reduced relative clause: ecologists studying [the possibility of] wolf recolonization
Two events occurred before the ecologists hypothesized.
I described those two events and labeled them "A" and "B," respectively.
We use past perfect to talk about events in the past that happened before a different, more recent event in the past.
Events A and B happened at different times.
A century and a half ago, wolves were removed from Washington.
Then the mesopredator (coyote) population exploded.
Can we use past perfect for two or more events that occurred at different times but before a clearly later-in-time event?
Absolutely yes. In fact, when timing or sequence is unclear or dense, we should do so.
Do sequence words mean that past perfect is unnecessary or optional and that we should rely only on simple past tense?
No.
In simple sentences in which sequence is very simple, very clear, and signified by words such as before, after, previously, and subsequently, you probably do not need to use past perfect.
Is it incorrect to use past perfect with sequence words? No.
The construction may not be ideal in sentences in which the time sequence is very clear, but it is not wrong.
A decade ago, such a sentence would not necessarily have been wrong, but would not likely have been the best answer.
Things have changed a bit.
I noted in a recent post that official questions in the last few years have contained both sequence words and past perfect.
In those official questions, despite the presence of a sequence word, I suspect that past perfect is used because the timeline is still hard to follow.
Such is the case in this question.
So you think like a test maker.
Aspirant to self: Self, this question tests verb tenses that describe events that occurred in the past.
Some of the events happened a long time before the other events.
This timing of events in this sentence is not very clear. I've read this thing three times and I finally figured out the timing.
Aha! If timing is difficult to discern even though time markers have been given, I should go with the verb tense that is designed to describe the earlier-in-time past events: past perfect . . . . the past of the past.
COMMENTS
Zain92 , PyjamaScientist (what a great username) , kantapong , dinubisht003 , and Ratisbon1993 , welcome to SC Butler.
nehasheela2 , Shaajiib , welcome to SC Butler, and I addressed your questions in my OE.
piyushluniya , the presence of sequence words does not necessarily make the use of past perfect "optional," though I've given you kudos because your question goes right to the heart of the matter and I appreciate your politeness.
zanto , you asked about the phrase "by killing coyotes."
On occasion, if we want to emphasize something in a short phrase, we can "split the verb" and insert the phrase.
To learn more about splitting the verb with a short phrase, [spoiler alert, official question], see my post by clicking here.
I honestly do not know whether GMAC would pit these two constructions against each other but believe a good chance of its writers doing so exists.
I am going to lock the topic for now.
I think it forces you to get outside rules that are by no means set in stone and to think about which verb most clearly expresses the chain of events in this complicated situation.
I may archive the question. I need to think about the matter.
Anyone who attempted this question gets kudos.
I respect bravery.
Stay safe.
Project SC Butler: Sentence Correction (SC1)
THE PROMPT
Quote:
→ Scientists hypothesized something in the past. The elimination of wolves and the mesopredator overpopulation both took place before this hypothesis.
The easiest way to make that fact about both prior events clear is to use past perfect for both.
→ Because the first part of the sentence is in the simple past tense, the correct word to refer to the future (in the past) is would and not will.
THE OPTIONS
Quote:
→ The use of will to refer to a future event in the past is incorrect. Use would instead.
→ The phrase wolves were should be wolves had been: the wolf elimination took place before the hypothesis, which is the latest event in time and is described by the simple past tense.
→ The word occurring should probably be that had occurred.
As this option stands, it erroneously intimates that the overpopulation [was continuously] occurring when wolves were eliminated [not continuous].
ELIMINATE A
Quote:
→ The elimination of wolves and the mesopredator overpopulation both took place before the hypothesis and hence probably require the past perfect tense had occurred and had been eliminated. See my extra notes and Notes, below.
→ If you are not sure, keep B and compare to C (after you eliminate the last two).
ELIMINATE B
Quote:
→ Correct.
→ This sentence correctly uses would to refer to a future event in the past.
→ It also uses the past perfect tense to describe the two earlier events.
KEEP
Quote:
→ The use of will to refer to a future event in the past is incorrect.
→ The phrase wolves were should be wolves had been because this wolf elimination took place before the hypothesis.
→ Bizarre verb tenses for the timeline.
In this option, the earliest event is written in simple past tense whereas the second-in-time event (mesopredator overpopulation) is written in past perfect!
ELIMINATE D
Quote:
→ The mesopredator overpopulation took place before the hypothesis and thus requires the past perfect tense had occurred.
→ The style is a bit strange. True, short phrases such as by killing coyotes can be placed between auxililary (would) and main verb (reverse). But the other options do not "stick" this phrase in the middle of the verb construction.
ELIMINATE E
The best answer is C.
Another strategy
Split #1: would is correct but will is not
Eliminate options A and D for using will.
When we talk about the "future in the past," we use X would happen.
Split #2: Compare the timelines of B, C, and E.
Choose the option whose verbs are designed to convey the timeline—not that just happen to do so if you can keep track of the time markers.
Option B:
A) wolves were eliminated a century before the ecologists hypothesized = wolves were eliminated 150 years ago
B) mesopredator overpopulation occurred = at some point in time . . . close to when wolves were eliminated?
C) ecologists hypothesized = 50 years ago
→ This option does not look terrible, but it seems odd that event B gets simple past tense because mesopredator overpopulation occurred after 150 years ago but before 50 years ago.
In other words, the mesopredator overpopulation comes before the hypothesis set down 50 years ago.
How do we best signal this pre-hypothesis timing of the mesopredator overpopulation?
We use had occurred to make it clear that overpopulation preceded the scientists' hypothesis.
After we think about this sentence for awhile, that fact seems obvious, but upon first reading, tracking on the timeline is hard. Make it easy.
Option C:
A) wolves had been eliminated a century earlier = wolves had been eliminated 150 years ago, before the mesopredator overpopulation and before the hypothesis
B) mesopredator overpopulation had occurred at some time in the past after the wolves had been eliminated but before the ecologists hypothesized
C) ecologists hypothesized 50 years ago
→ This option seems better than B.
Past perfect verb tense is used to describe "past of the past" events such as A and B here, both of which occurred before the hypothesis.
Can past perfect be used for two or more events in the past of the past that did not occur at the same time? Of course!
The immigrant children were exhausted because they had traveled for weeks, been without enough food or water, and not slept for nearly two days.
Option E:
A) wolves had been eliminated= sometime before the hypothesis and before the mesopredator overpopulation
B) mesopredator overpopulation occurred = when? contemporaneously with the scientists hypothesis? No.
Mesopredator overpopulation is in the past of the past.
C) ecologists hypothesized
Compare these three.
Which one uses the verbs most efficiently or in a way that is most true to their purpose?
Option E is the worst of the lot because it contains a mixed or garbled message: two past of the past events, but one is described by one tense and the other, by another tense.
Eliminate E.
Now, Option B or C?
Err on the side of clarity.
Using past perfect tense with sequence words is okay when the sequence words are not terribly clear and the sentence is dense.
Pick option C.
NOTES
• Sequence of events
A) 150 years ago: wolves were eliminated from Washington State
Sometime after #1 but BEFORE 50 years ago:
B) the population of mesopredators, including coyotes, grew too large
C) 50 years ago: ecologists were studying (contemplating) wolf recolonization.
The ecologists explored the idea of moving wolves from Canada down to Washington State
→ notice: "ecologists [WHO WERE] studying [the possibility of] wolf recolonization"
D) 50 years ago: ecologists hypothesized that bringing wolves from Canada to Washington state would reverse the problem of mesopredator overpopulation.
The ecologists hypothesized that this reversal would occur because wolves would kill coyotes. Apparently, coyotes constituted many or maybe all of the mesopredators whose population had grown too much.
Events C and D happened pretty much simultaneously. Both events are described in the nonunderlined portion of the sentence.
Ecologists studying is a reduced relative clause.
Relative clause: ecologists who were studying [the possibility of] wolf recolonization
Reduced relative clause: ecologists studying [the possibility of] wolf recolonization
Two events occurred before the ecologists hypothesized.
I described those two events and labeled them "A" and "B," respectively.
We use past perfect to talk about events in the past that happened before a different, more recent event in the past.
Events A and B happened at different times.
A century and a half ago, wolves were removed from Washington.
Then the mesopredator (coyote) population exploded.
Can we use past perfect for two or more events that occurred at different times but before a clearly later-in-time event?
Absolutely yes. In fact, when timing or sequence is unclear or dense, we should do so.
Do sequence words mean that past perfect is unnecessary or optional and that we should rely only on simple past tense?
No.
In simple sentences in which sequence is very simple, very clear, and signified by words such as before, after, previously, and subsequently, you probably do not need to use past perfect.
Is it incorrect to use past perfect with sequence words? No.
The construction may not be ideal in sentences in which the time sequence is very clear, but it is not wrong.
A decade ago, such a sentence would not necessarily have been wrong, but would not likely have been the best answer.
Things have changed a bit.
I noted in a recent post that official questions in the last few years have contained both sequence words and past perfect.
In those official questions, despite the presence of a sequence word, I suspect that past perfect is used because the timeline is still hard to follow.
Such is the case in this question.
So you think like a test maker.
Aspirant to self: Self, this question tests verb tenses that describe events that occurred in the past.
Some of the events happened a long time before the other events.
This timing of events in this sentence is not very clear. I've read this thing three times and I finally figured out the timing.
Aha! If timing is difficult to discern even though time markers have been given, I should go with the verb tense that is designed to describe the earlier-in-time past events: past perfect . . . . the past of the past.
COMMENTS
Zain92 , PyjamaScientist (what a great username) , kantapong , dinubisht003 , and Ratisbon1993 , welcome to SC Butler.
nehasheela2 , Shaajiib , welcome to SC Butler, and I addressed your questions in my OE.
piyushluniya , the presence of sequence words does not necessarily make the use of past perfect "optional," though I've given you kudos because your question goes right to the heart of the matter and I appreciate your politeness.
zanto , you asked about the phrase "by killing coyotes."
On occasion, if we want to emphasize something in a short phrase, we can "split the verb" and insert the phrase.
To learn more about splitting the verb with a short phrase, [spoiler alert, official question], see my post by clicking here.
I honestly do not know whether GMAC would pit these two constructions against each other but believe a good chance of its writers doing so exists.
I am going to lock the topic for now.
I think it forces you to get outside rules that are by no means set in stone and to think about which verb most clearly expresses the chain of events in this complicated situation.
I may archive the question. I need to think about the matter.
Anyone who attempted this question gets kudos.
I respect bravery.
Stay safe.
03 Jul 2021, 21:27
Kudos
Bookmarks
A) by killing coyotes, wolves will reverse the mesopredator overpopulation occurring when wolves were
the researchers hypothesis was made in the past. Hence the use of "will" is incorrect
B) by killing coyotes, wolves would reverse the mesopredator overpopulation that occurred when wolves were
elimination of wolves should take past perfect.
C) by killing coyotes, wolves would reverse the mesopredator overpopulation that had occurred when wolves had been
Overpopulation occurred after the wolves had been eliminated. So there is no need to use past perfect with overpopulation. Rather elimination of wolves should take past perfect.
D) wolves, by killing coyotes, will reverse the mesopredator overpopulation that had occurred when wolves were
same as A.
E) wolves would, by killing coyotes, reverse the mesopredator overpopulation that occurred when wolves had been
CORRECT
the researchers hypothesis was made in the past. Hence the use of "will" is incorrect
B) by killing coyotes, wolves would reverse the mesopredator overpopulation that occurred when wolves were
elimination of wolves should take past perfect.
C) by killing coyotes, wolves would reverse the mesopredator overpopulation that had occurred when wolves had been
Overpopulation occurred after the wolves had been eliminated. So there is no need to use past perfect with overpopulation. Rather elimination of wolves should take past perfect.
D) wolves, by killing coyotes, will reverse the mesopredator overpopulation that had occurred when wolves were
same as A.
E) wolves would, by killing coyotes, reverse the mesopredator overpopulation that occurred when wolves had been
CORRECT
