First recollect the IF... THEN .. structure for the following cases:

1. IF simple present THEN simple future.
2. IF hypothetical subjunctive THEN conditional (would / could etc.).


Now consider a sentence in the first structure:
If it strikes Earth, it will probably not cause planet-wide destruction.

How would you convert this sentence to a future event not likely to happen (i.e., the second structure):
If it struck Earth (OR if it were to strike Earth), it would probably not cause planet-wide destruction.

Note that "would" in the THEN clause is a grammatical requirement to match the IF clause. Therefore in this case "would probably" is not considered redundant.

In the previous example, there is no IF.. THEN.. structure to justify the use of "would". In such standard cases, "will probably" is correct.

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planet-wide destruction.

So the scientists found two facts about the asteroid. These two facts are connected by “and”. The first fact begins with “that”. However, the second fact does not begin with “that”. This leads to parallelism error in the sentence.

A. and, if it strikes Earth, it can do tremendous damage to part of the planet but: Incorrect for the reason stated above.

B. and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would: Incorrect. Repeats the same parallelism error of Choice A.

C. and that, if it were to strike Earth, could do tremendous damage to part of the planet but would: Correct.

D. and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would: Incorrect. This choice has ungrammatical structure. The “if” clause is unnecessarily in passive voice. The “then” clause is still in active voice. This makes it seem that Erath could only partly damage the planet. This meaning is illogical.

E. and that, if it strikes Earth, it could experience a tremendous amount of damage but: Incorrect. The pronoun “it” in the “then” clause refers to “asteroid”, meaning that the asteroid could experience damage. This is certainly not the intended meaning of the sentence.

I read this explanation on the e-gmat forum and am posting it here for the benefit of the fellow students.
Hope this helps everyone.

IMO,

It's a question on parallelism. ' That' has to be repeated in the second part of the sentence( that is.........'and that' is.....).

A, B are out. E changes the meaning and usage of 'it' is ambiguous. D is awkard and is also in the past tense

I'll go with C

Cheers,
unplugged

But in C, isnt the use of 'that' and 'it' redundant? both are referring to asteroid!

"it were to strike earth" is a modifier clause to "that". Hence, the use of "it" is ok.

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and that,< if it were to strike Earth>, could do tremendous damage to part of the planet but would probably not cause planetwide destruction

remove the sentence between commas and read.. then C makes sense.

that is about half a mile wide and that could do tremendous..

that is necessary to maintain parallelism and correct usage.

if it were to strike Earth , that would probably not cause planet wide destruction --> correctly describes the hypothetical situtation.


"if it were to strike Earth" --> i don't see the best way to rewrite this statement without using "it". If you can try it


and, if it strikes Earth, it can do tremendous damage to part of the planet but

I agree that in E .. "it" after comma is redundant.

A. and, if it strikes Earth, it can do tremendous damage to part of the planet but -- it can refer back to earh or asteroid.. not clear..Hence, incorrect.

B. and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would -- it can refer to part of the planet, asteroid or earth.. not clear..Hence, incorrect.

C. and that, if it were to strike Earth, could do tremendous damage to part of the planet but would -- correct..subjunctive mood for hypothetical situations..

D. and that, if earth struck by it can do part of the planet tremendous damage, but it would -- Passive..seems like earth is causing the damage.Hence, incorrect.

E. and that, if it strikes earth, it could experience a tremendous amount of damage but --Who will exprience damage ? earth or asteroid..not clear...hence, incorrect.

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planetwide destruction.


A. and, if it strikes Earth, it can do tremendous damage to part of the planet but needs and *that*
B. and, if it would strike Earth, part of the planet could experience a tremendous
amount of damage but it would needs and *that*
C. and that, if it were to strike Earth, could do tremendous damage to part of the
planet but would
D. and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would passive voice, requires subjunctive to describe the possible event
E. and that, if it strikes Earth, it could experience a tremendous amount of damage but present tense "strikes" is not appropriate to describe the possible event

Sayantan, Im confused. Isnt there redundancy in C because both 'would' and 'probably' are used?

From what I knew, in doubtful mood, modals are used. However, recently I came across a question in which the right answer (B) did not use the modal 'will' because the word 'probably' was already used hence linking verb 'will' was used instead; you helped me understand this concept. Following is that question -

Due to the fact that Jordan wrecked Bono's station wagon during a road trip last summer, she has not been and probably never would be allowed to drive her father's car.

(A) has not been and probably never would be allowed to drive
(B) has not been allowed to drive and probably never will be allowed to drive
(C) has not and probably never would be allowed to drive
(D) has not and probably will never be allowed to drive
(E) has not and probably never will be allowed to drive

Can you help with this paradox?

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planetwide destruction.

A. and, if it strikes Earth, it can do tremendous damage to part of the planet but
B. and, if it would strike Earth, part of the planet could experience a tremendous No ||ism
amount of damage but it would
C. and that, if it were to strike Earth, could do tremendous damage to part of the planet but would[/color]
D. and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would
E. and that, if it strikes Earth, it could experience a tremendous amount of damage but
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Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planet-wide destruction.

(A) and, if it strikes Earth, it can do tremendous damage to part of the planet but
correct structure That X ,and That Y - parallelism issue : Incorrect

(B) and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would
same as A : Incorrect
(C) and that, if it were to strike Earth, could do tremendous damage to part of the planet but would
Correct structure 'That X ,and That Y' & use of 'were' for hypothetical situation is correct.
(D) and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would
use of simple present in If.. clause for hypothetical situation is wrong : Incorrect
(E) and that, if it strikes Earth, it could experience a tremendous amount of damage but
'It' has antecedent issue . Asteroid or earth ; use of simple present in If.. clause for hypothetical situation is wrong : Incorrect


Experts pls. comment

Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planetwide destruction.

A. and, if it strikes Earth, it can do tremendous damage to part of the planet but - parallelism issue - we need a that after and
B. and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would - same as A
C. and that, if it were to strike Earth, could do tremendous damage to part of the planet but would - Correct
D. and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would - If is in passive but then part is in active voice
E. and that, if it strikes Earth, it could experience a tremendous amount of damage but - usage of strikes is incorrect ; as per sentence structure it illogically refers to asteroid

Answer C
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daagh Skywalker18 AjiteshArun
I just wanted to know about the if else construction in OA: C
isn't it required before could ?

What is the if else construction in C?

Posted from my mobile device
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No, because in this construction, the that does what something like an it would normally do in a different construction. Look at what that part of C says:
... an asteroid... that, if it were to strike Earth, could do tremendous damage to part of the planet...

We have a relative clause here. Let's try reading it without the if:
... an asteroid... that could do tremendous damage to part of the planet...

Here the verb could do takes that as its subject. We can't supply another subject like it here. Take a look at the following sentence and check whether it sounds good:
... an asteroid... that it could do tremendous damage to part of the planet...

Now let's attach an if to include the conditional:
... an asteroid... that could do tremendous damage to part of the planet, if it were to strike [the planet]...

Option C just shifts the if clause to the beginning of the that clause.
... an asteroid... that, if it were to strike [the planet], could do tremendous damage to part of the planet...

Another example:
A student who, if he studies hard, he can get a good score...
vs.
A student who, if he studies hard, can get a good score...
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[quote="drdas"]Scientists have identified an asteroid, 2000 BF19, that is about half a mile wide and, if it strikes Earth, it can do tremendous damage to part of the planet but probably not cause planetwide destruction.


A. and, if it strikes Earth, it can do tremendous damage to part of the planet but

B. and, if it would strike Earth, part of the planet could experience a tremendous amount of damage but it would

C. and that, if it were to strike Earth, could do tremendous damage to part of the planet but would

D. and that, if Earth is struck by it, can do part of the planet tremendous damage, but it would

E. and that, if it strikes Earth, it could experience a tremendous amount of damage but

parallelism is a concept which is easy to explain but hard to apply. this case is typical on English language. in this case, some person can know English grammar but can not write English sentence

at this point, we need skills to write. skill is the thing more "expensive" than knowledge . skills is something higher than knowledge.

in parallelism problem, 3 ideas presented by 3 clauses or 3 actions presented by 3 verb are shown. for example, the 3 ideas and actions can be A, B and C

the answer choice will show us many possibility
A, B//C
A//B , C
A//C, B

we need to find out which ideas or actions should be parallel with which ideas action.

we have 3 actions here, have identified, is about half+
and do damage

it is not logic to parallel "have identifies " with "do damage" as choice A do
logically, "strike " and "do damage" should be paralel and this meaning parallelism should be in a parallel form.

in choice D, "that can do" and "but it would" are not parallel in form. so, this is wrong.

in choice C, "experience" is parallel with "have identifiec " grammatically but they can not be parrallel logically . C is wrong

Where do we use "IT were", I eliminated option C because it was using were with it? Please Explain the concept behind it

This is something used in hypothetical statements. Let's say that there is an asteroid that, to the best of your knowledge, is not going to strike Earth, but you want to discuss what would happen if it did (strike Earth). That is, you want to discuss a hypothetical situation.

Look at the main verb used in the if statement. If you see any of the forms of be (be, is, am, are, was, were, been, and being), remove any option that does not use were.

1 If the asteroid struck Earth... ← This is fine. There is no reason to look for a were because there is no be form here.

2 If the asteroid is to strike Earth... ← This is not correct. Is is a form of be, and this is not a "real" situation.
3 If the asteroid was to strike Earth... ← This is not correct. Was is a form of be, and this is not a "real" situation.
4 If the asteroid was any larger... ← This is not correct. Was is a form of be, and this is not a "real" situation.

5 If the asteroid were to strike Earth... ← This is fine.
6 If the asteroid were any larger... ← This is fine.
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Why is ellipsis not in play here?
Shouldn't it repeat "that" since "and" is a one-word parallelism marker?