astronomers had/have discovered 17 nearby stars

[late4thing]

By 1999, astronomers had discovered 17 nearby stars that are orbited by planets
about the size of Jupiter

A: had discovered 17 nearby stars that are orbited by planet
B: had discovered 17 nearby stars with planets orbiting them that were
C: had discovered that there were 17 nearby stars that were orbited by planets
D: have discovered 17 nearby stars with planets orbiting them that are
E: have discovered that 17 nearby stars are orbited by planets

I understand why the present perfect is wrong but hoping an expert can explain the reasoning between the other three answer choices.

[GMATGuruNY]

By 1999, astronomers had discovered 17 nearby stars that are orbited by planets
about the size of Jupiter

A: had discovered 17 nearby stars that are orbited by planet
B: had discovered 17 nearby stars with planets orbiting them that were
C: had discovered that there were 17 nearby stars that were orbited by planets
D: have discovered 17 nearby stars with planets orbiting them that are
E: have discovered that 17 nearby stars are orbited by planets

D and E: By 1999, astronomers have discovered
Here, have discovered (present perfect) cannot serve to express an action completed by 1999 (in the PAST).
Eliminate D and E.

A VERBing modifier serves to express an action that takes place at the same time as the MAIN VERB.
In B, the usage of orbiting seems to imply that planets were ORBITING the 17 nearby stars only IN THE PAST -- when the stars were DISCOVERED by astronomers.
Since the intended meaning is that planets are STILL orbiting the 17 nearby stars, eliminate B.

C: that there were 17 stars
Here, the usage of were seems to imply that the 17 nearby stars no longer exist.
Since the intended meaning is that the 17 nearby stars DO still exist, eliminate C.

The correct answer is A.

[Crystal W]

Can you tell me what does "about the size of Jupiter" modify? Stars or Planets?
Thanks in advance!

[MartyMurray]

Can you tell me what does "about the size of Jupiter" modify? Stars or Planets?
Thanks in advance!

stars is modified by that are orbited by planets.

What kind of stars are they? They are stars that are orbited by planets.

about the size of Jupiter modifies planets.

What kind of planets are they? They are planets about the size of Jupiter.

In this case, really the only way to tell which modifier modifies which noun is to notice the placement of the modifiers. Each modifier is directly after what it modifies.

Also, if you consider the construction and meaning of the sentence, you can notice there is no logical reason to feel that it conveys that the stars are about the size of Jupiter. Right? So without having to get technical, you can tell that about the size of Jupiter does not modify stars.

[nk18967]

C: that there were 17 stars
Here, the usage of were seems to imply that the 17 nearby stars no longer exist.
Since the intended meaning is that the 17 nearby stars DO still exist, eliminate C.

The correct answer is A.

Hi Mitch,

How do we know/ how can we tell what exactly the intended meaning is? Maybe the starts don't exist anymore?
There could have been a tense issue in choice A?
Is there any other reason to eliminate C?

Thanks!

[GMATGuruNY]

Hi Mitch,

How do we know/ how can we tell what exactly the intended meaning is? Maybe the starts don't exist anymore?

If the original sentence conveys a meaning that make sense, this meaning should be considered the intended meaning.
Here, the meaning conveyed by A makes sense.
Since A implies that the 17 discovered stars still exist, this meaning should be considered the intended meaning.

There could have been a tense issue in choice A?

Since A is the correct answer choice, there is no tense error in A.

Is there any other reason to eliminate C?

Generally, the past perfect (had + VERBed) serves to express a past action completed before another past event.
C: Scientists had discovered that there were 17 nearby stars.
Since the usage of the past perfect (had discovered) seems to imply that the discovery of the 17 nearby stars was completed before the 17 nearby stars existed.
This sequence is illogical.
Eliminate C.

[solitaryreaper]

C: Scientists had discovered that there were 17 nearby stars.
Since the usage of the past perfect (had discovered) seems to imply that the discovery of the 17 nearby stars was completed before the 17 nearby stars existed.
This sequence is illogical.
Eliminate C.

Hi Mitch,

Though I agree that -"that there were 17 nearby stars that were orbited by planets" piece is wrong(in its individuality).
But in my opinion usage of past perfect is necessary/correct in option C in order to imply the intended meaning.

It is necessary to point the timeline of the discovery of stars- an act that had finished before a point event i.e. year 1999 (expressed by By 1999,)

Please correct me if there're gaps in my understanding.

Regards
SR

[GMATGuruNY]

C: Scientists had discovered that there were 17 nearby stars.
Since the usage of the past perfect (had discovered) seems to imply that the discovery of the 17 nearby stars was completed before the 17 nearby stars existed.
This sequence is illogical.
Eliminate C.

Hi Mitch,

Though I agree that -"that there were 17 nearby stars that were orbited by planets" piece is wrong(in its individuality).
But in my opinion usage of past perfect is necessary/correct in option C in order to imply the intended meaning.

It is necessary to point the timeline of the discovery of stars- an act that had finished before a point event i.e. year 1999 (expressed by By 1999,)

Please correct me if there're gaps in my understanding.

Regards
SR

Your thinking is correct.
The usage of by 1999 requires the past perfect tense (had discovered).
The error in C is that the tense of the following verb -- were -- conveys an illogical sequence, as discussed in my post above.

[solitaryreaper]

Thanks for the confirmation Mitch - that really helps!

[[email protected]]

Hello Everyone!

Let's tackle this question, one thing at a time, and narrow it down to the correct choice! First, let's take a quick glance over the options and highlight any major differences we can find in orange:

By 1999, astronomers had discovered 17 nearby stars that are orbited by planets about the size of Jupiter.

(A) had discovered 17 nearby stars that are orbited by planets
(B) had discovered 17 nearby stars with planets orbiting them that were
(C) had discovered that there were 17 nearby stars that were orbited by planets
(D) have discovered 17 nearby stars with planets orbiting them that are
(E) have discovered that 17 nearby stars are orbited by planets

After a quick glance over the options, we found 2 places we can focus on:

1. had discovered / have discovered (Verb Tense)
2. How each option ends (Modifiers / Verb Tense / Meaning)

Let's start with #1 on our list because it will eliminate 2-3 options right away. This is a pretty easy one because it has to do with verb tenses! If we look at the entire sentence for clues, we can figure out which verb tense we need:

By 1999, astronomers had discovered 17 nearby stars that are orbited by planets about the size of Jupiter.

Since all of the discoveries were started AND FINISHED in the past, it makes the most sense to use the past perfect tense! If we were talking about discoveries that were started in the past, but were still being made today, it would make sense to use present perfect tense. Let's see how our options stack up:

(A) had discovered 17 nearby stars that are orbited by planets
(B) had discovered 17 nearby stars with planets orbiting them that were
(C) had discovered that there were 17 nearby stars that were orbited by planets
(D) have discovered 17 nearby stars with planets orbiting them that are
(E) have discovered that 17 nearby stars are orbited by planets

We can easily eliminate options D & E because they use the present perfect instead of the past perfect verb tense.

Now that we have things narrowed down, let's tackle #2 on our list: how each option ends. We need to make sure that any modifiers we find work (hint: they'll start with the word "that"), and make sure any verbs we find make sense:

(A) had discovered 17 nearby stars that are orbited by planets

This is CORRECT! It makes more sense to say that the stars are currently orbited by planets. The planets were discovered orbiting stars in 1999, but it's safe to say they're still doing so today.

(B) had discovered 17 nearby stars with planets orbiting them that were

This is INCORRECT because the use of the past tense "were" doesn't work here. The planets are STILL the size of Jupiter - that didn't change after 1999. Since we're talking about a phenomenon that was discovered in the past, but still goes on today, it makes more sense to use present tense verbs here.

(C) had discovered that there were 17 nearby stars that were orbited by planets

Again, this is INCORRECT because the use of past tense here doesn't convey the correct meaning. The discoveries were made in the past, but the planets and stars are still behaving the same way today!


There you have it - option A was the correct choice all along! If we focus on the either/or differences between options, it's easy to eliminate wrong ones quickly!


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