GMATGuruNY wrote:djaytg wrote:To develop more accurate population forecasts,
demographers would have to know a great deal more than they
do now about the social and economic determinants of
fertility.
Would is used to refer to the future in the past
But here would is referring to the future in relation to the present
Can someone please explain?
Here,
would serves to indicate the SUBJUNCTIVE mood.
One purpose of the subjunctive is to indicate an event that is HYPOTHETICAL.
GOAL: To develop more accurate forecasts.
PRESENT PROBLEM: The demographers do not know enough.
There is one way that demographers could -- HYPOTHETICALLY, in the future -- develop more accurate forecasts:
They WOULD HAVE TO KNOW MORE than THEY ACTUALLY DO KNOW now.
Acording to "advance learner's grammar" book, "would" can be used to show about a desire which is IMPOSSIBLE TO FULLFILL. for example,
I would like to be a man ( I am a girl)
I like to be a man ( I am a boy and can be a man next year)
I do not see "would " is used for hypethetical (unreal) action. But I guess Mint Hunch is correct.
the point is that in this sentence, author means that the knowing is unreal. we do not need to identify the action is possible or impossible, real or hypothetical,
we only need to know that both the meaning is acceptable. other error will lead us to the correct choice.
it is clear that grammar books do not explain clearly about this use of would, about hypothetical/impossible action which "would" present.
gmat do not test this identifying.
"would" is also used to say about a present request but is more polite than "will"
"would" is also used to say about future, viewed in present but is less likely than "will". for example: now I say it will rain. Now, I say it would rain. the second sentence is less certain than the first sentence. "would" in the second sentence is not future in the past: yesterday I said it would rain.
