Will VS Would

[Guest]

Hi

Can someone highlight the difference between WIll and Would? I've got confused with this Q ( Gmat Prep )

If current trends continue, by the year 2010 carbon emissions in the United States will soar to a level more than one-third higher than were those in 1990, according to official projections.
A. will soar to a level more than one-third higher than were those
B. will soar to a level more than one-third higher than that
C. would soar to a level more than one-third higher than is was
D. would soar to a level more than one-third higher than those
E. would soar to a level more than one-third higher than they were

I picked E ( and eliminated A and B)

[RA]

Is the OA (B)

[Guest]

yes - OA is A - but why

[RA]

I am assuming you meant that the correct answer is (B)not (A). Please confirm

"would" is used if the sentence is talking about the future in past tense. Since the mentioned sentence is talking about the future in present tense (current trends continue....) "will" is the appropriate choice.

[guest]

Yes - sorry. OA is B

[esledge]

Good explanation by RA, but I am not sure you can look solely at the present tense "continue" for the reason.

Another way of distinguishing is that "will" applies to predictions, while "would" applies to hypotheticals. Another use of "would" is as an alternative to "used to."

Examples:
If current trends continue, carbon emisions will soar... (prediction)
If we take action, carbon emissions will not soar as feared... (prediction)
If we had not taken action, carbon emissions would have soared... (hypothetical)
Carbon emissions would soar during rush hour, until traffic was reduced... ("used to" replacement)