Galileo did not invent the telescope, but on hearing, in 1609, that su

Dear Friends,

Here is a detailed explanation to this question-

Concepts tested here: Tenses + Grammatical Construction + Awkwardness/Redundancy

• 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".
• Information vital to the core meaning of the sentence must not be placed between comas.
• “being” is only to be used when it is part of a noun phrase or represents the passive continuous verb tense; the use of passive continuous must be justified in the context.

A: Correct. This answer choice acts upon the independent subject “Galileo” with the active verbs “invent” and “built” to form a complete thought, leading to a complete sentence. Further, Option A correctly uses the simple past tense to refer to an action that concluded in the past. Additionally, Option A avoids the grammatical construction error seen in Option C, as it only places extra information between commas. Besides, Option A is free of any awkwardness/redundancy.

B: This answer choice incorrectly uses the past perfect tense verb “had not invented” to refer to an action 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". Further, Option B needlessly uses the passive verb construction “having been made”, leading to awkwardness and redundancy.

C: This answer choice incorrectly uses the past perfect tense verb “had not invented” to refer to an action 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". Further, Option C incorrectly places information vital to the core meaning of the sentence – the fact that Galileo did not invent the telescope – between two commas; please remember information vital to the core meaning of the sentence must not be placed between comas.

D: This answer choice fails to form a complete sentence; “invent”, “hearing”, and “had been made” are all parts of modifying phrases, meaning there is no active verb to act upon “Galileo”.

E: This answer choice redundantly uses “Even though” alongside “but”, rendering it awkward and needlessly wordy. Further, Option E incorrectly uses the word “being”, leading to further awkwardness and redundancy; remember, “being” is only to be used when it is part of a noun phrase or represents the passive continuous verb tense; the use of passive continuous must be justified in the context; “being” is only to be used when it is part of a noun phrase or represents the passive continuous verb tense; the use of passive continuous must be justified in the context.

Hence, A 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 (~2 minutes):



To understand the concept of "Extra Information Between Commas" on GMAT, you may want to watch the following video (~1 minute):



All the best!
Experts' Global Team

The answer is A .
But for the qn what is wrong with two hads..
The invention is a one time activity and so past perfect tense shouldn't be used.
It should be ..he didn't invent..but not he had not invented(Its not continuing).
We are talking abt an instance of an event(invention), which didn't take place.

Thanks,

B. no reason to use past perfect tense.
C. redundant subject - Galileo and he
D. subject not present
E. 1609 is wrong. we need a preposition.

E: "even though" together with " but" is redundant--> out
D: "even though" forms two related clauses, we can't find the subject for th 2nd clause in D--> out.
B: yup, the use of past perfect is unsuitable here-->out
C: every part is disorderly displaced---> out.
A it is.

Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he quickly built his own device from an organ pipe and spectacle lenses.

1. "Galileo did not invent the telescope" is an independent clause.
2. "but on hearing, in 1609, that such an optical instrument had been made" is a dependent clause.
3. "he quickly built his own device from an organ pipe and spectacle lenses" is an independent clause.

Sequense of events: "such an optical instrument had been made" occured before "Galileo did not invent the telescope" and "he quickly built his own device from an organ pipe and spectacle lenses". so

1. "Galileo did not invent the telescope" is in past perfect tense.
2. "but on hearing, in 1609, that such an optical instrument had been made" is in simple past tense.
3. "he quickly built his own device from an organ pipe and spectacle lenses" is in simple past tense.

so choices other than A violets these rules and are incorrect....

I would go with A.

A: Correct
B: wrong use of verb tenses -- had not invented implies that he will invent the telescope in the future
C: Galileo, on hearing that such an optical instrument had been made, he -- totally wrong
D: missing "he" at the end
E: "even though" and "but" are redundant

B, D -- are out.. "he" is missing before "quicklly"
C -- Galileo,...,he .. he is redundant
E. eventhough .. but --> redundant and "being made" --> wrong

A -- looks better.

Galileo didn't invednted (pastense),... optical instrument had been made.(past perfect -- passive voice.)

pefect..

Lets use POE

You need had been -because instrument was built first and then Galileo heard
so, B and E - gone

OK , A,C and D

D - I like D if there was a ' he ' in the end , without that this sentence goes for a toss

C is no good as well , if you remove all non-required clauses - you are left with Galileo and he . Also , this sentence uses two had been - not a good way to describe sequence of events - gone

A is the answer

A.

I had a slightly different approach.

Besides C, D and E having all sorts of errors, I would eliminate C, D and E because even though would change the context slightly.
The original sentence emphasizes the fact that he wasn't the first person to invent the telescope. Inserting even though instead of but, the passage seems to emphasize the fact he did made the telescope and sounds more forgiving about the fact he wasn't the first.

Having been made on B is obviously wrong. so I went with A.

Does my reasoning make sense or valid? let me know.

The modifiers CANNOT modify across "and", "but" etc.
The modifier in the status quo is "but on hearing". So it will modify the clause that comes just after this modifier WHEREAS without "but" in modifier, it seems that "on hearing" can modify either side of it, creating ambiguity.
B implies that Galileo WAS the inventer because the other device was being made; lacks the subject; is a run on.
C and D have modifier ambiguity.; D lacks the subject.
E changes the meaning by implying that the other device was still being made WHEREAS the original intent says that the other device had already been made.

Answer: A


(A) Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he quickly built his own device...

A is made up of two independent clauses interlinked by "BUT"
(1) Galileo did not invent the telescope
(2) On hearing that such an optical instrument had been made, he quickly built his own device.

The verb tenses are also parallel in the two interlinked independent clauses:
(1) did not invent (simple past)
(2) built (simple past)

The verb on the "that such an optical instrument had been made" is also correct because it uses "had been made" to emphasize that this is a past event before another past event "built"

"on hearing that such..." also correctly modifies the subject "he"

Why the other sentences are wrong?

1. (B) and (E) are out!

Notice the split up of the 5 sentences on the verb usage: (B) "having been made", (E) "being made", and
(A,C,D) "had been made". The making of the telescope happened in 1609 so this calls for a past tense. Hence, B and E are out.


2. (C) is also out!

SENTENCE: Galileo, even though he had not invented the telescope, on hearing, in 1609 that such an optical instrument had been made, he

Let's re-arrange. Even though he had not invented the telescope, Galileo on hearing in 1609 that such an optical instrument had been made, he built...

The only clause with the verb is "even though he had not, ... , he built..." What's wrong with this? "Galileo on hearing in 1609..." is a sentence fragment between a dependent clause and an independent clause. This is a distorted structure.

3. (D) is also wrong.

Even though..., on hearing that such ..., [HE] quickly built...

Let's say "Even though ..., on hearing, in 1609 that such ..." is the dependent clause. There should be an independent clause. But "quickly built..." has no subject "he"

Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he quickly built his own device from an organ pipe and spectacle lenses.

A. Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he Best choice - all verbs work together

B. Galileo had not invented the telescope, but when he heard, in 1609, of such an optical instrument having been made, Wrong - second clause is a fragment; no need for past participle + "invented" because the sentence is clear without it.

C. Galileo, even though he had not invented the telescope, on hearing, in 1609, that such an optical instrument had been made, he Wrong - two subjects in the sentence; part participle + "invented" is not needed because there is no need to distinguish the past; wordy and awkward.

D. Even though Galileo did not invent the telescope, on hearing, in 1609, that such an optical instrument had been made, Wrong - sentence is a fragment without a subject.

E. Even though Galileo did not invent the telescope, but when he heard, 1609, of such an optical instrument being made, he Wrong - multiple modifiers make the sentence wordy; "being made" indicates a progressive tense, altering the meaning of the sentence.

IMO A

Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he quickly built his own device from an organ pipe and spectacle lenses.

A. Galileo did not invent the telescope, but on hearing, in 1609, that such an optical instrument had been made, he : Correct Choice

B. Galileo had not invented the telescope, but when he heard, in 1609, of such an optical instrument having been made, - he absent from 2nd clause and having been made is wrong

C. Galileo, even though he had not invented the telescope, on hearing, in 1609, that such an optical instrument had been made, he - Verb failed to show time sequence

D. Even though Galileo did not invent the telescope, on hearing, in 1609, that such an optical instrument had been made, - He absent from 2nd clause

E. Even though Galileo did not invent the telescope, but when he heard,in 1609, of such an optical instrument being made, he - Use of Even though and but is redundant

"but" is a co-ordinating conjunction. So "but" should introduce an independent clause. So my question is:

but on hearing, in 1609, that such an optical instrument had been made, he quickly built
Then the entire portion marked in bold acts as a modifier for the subject "he" and the verb "built". Is that it?

"But" does not necessarily join two independent clauses. Like "and", it can be used to join nouns, verbs, participles, etc.

Not John, but Jack is responsible for the accident. (2 nouns joined)
I will not sleep but work during this night. (2 verbs are joined)

Nonetheless in option A two independent clauses are joined:
Galileo did not invent, but he quickly built.

("Eliminate middlemen" as Manhattan SC guide suggests.)

"on hearing......had been made" is a modifier.

If one is clear about fragmentation and redundancy in a sentence, then he or she can sail through most of this topic with ease.

A is flawless.

B Had not invented is not correct 2. The main clause in the complex sentence does not have a subject.

C has redundancy with two subjects Galileo and he and a fragmentation with no predicate for the subject Galileo.

D is a fragment with no subject for the main clause.

E has redundancy since the coordinator 'but' and the subordinator 'even though' bring about out the same effect.

I really hate it when people post on a forum discussing an answer and call the right answer "flawless" How does that help anyone? And "A" is not flawless. It's a very flawed correct answer, but I am not saying it isn't correct.

Let's analyze the sentence

"Galileo did not invent the telescope", Nothing wrong with this. Has a subject past verb and object



"but on hearing, in 1609," This is very awkward also it's very unclear that this is a coordinating conjunction at first. It only becomes clear after reading. Also it's sloppy to use a but clause and then use a subordinating conjunction right after in "That":


"that such an optical instrument had been made," . So sloppy to start a coordinating conjunction with a "that clause"

he quickly built his own device from an organ pipe and spectacle lenses. This makes sense only if we assume the but is a coordinating conjunction and the that began a subordinating conjunction therefore the "he" part doesn't make a double subject.


It's very easy to read the but as a comparison and not a coordinating. They do use a comma though to give you a hint. However, I would hardly call starting a coordinating conjunction with a subordinating as flawless writing. That is a crappy response. It's a very crappy sentence even if it's correct. And no one would write like this, where they use a past verb, a participle, a past perfect and a past.