All possible uses of WOULD

This question is very difficult.  In fact, all questions which ask for a complete list of all possible cases of anything are very difficult.  People can give you a list of the usages they can think of, but there's never a guarantee that it's a list of all possibilities.  A textbook or even a series of textbooks might be necessary to answer your question.  Certainly, a single post on a forum is not likely to answer it.

Questions about would are particularly difficult because it is a function word.  It has no real definition in the way that the words table or dog can be defined. 

ravikumarkargam

Can I use it in the context of possibility (not quite sure) situations?

You're asking if you can use would in the context of doubt.  Yes, you can, as in the first example you give:

It is not known -- that is, it is doubtful -- whether the Fed would now change course ... 

You can paraphrase would now change as is now willing to change because would sometimes involves willingness.

It is doubtful whether the Fed is now willing to change course ... 

_____

ravikumarkargam

or what form such aid WOULD take.

Here you have a second conditional; the if clause is implicit, thus:

What form would such aid take, if the Fed [were to provide / provided] the capital? 

_____

In your second example, a "mixed conditional", it would be might be paraphrased as it may be called or it may be judged to be or it may be considered.

If the Fed intervenes, it [would be / may be judged to be / may be called / may be considered] an eleventh-hour bailout ....

Here the use of would instead of will makes the statement somewhat more remote, almost as if we weren't talking about the bailout directly, but indirectly about how to consider it.  The definiteness of will does not seem suitable in this context.  The use of will makes it seem that this is a future event, whereas, in fact, it's a situation in the present, looked at from the perspective of what we should call it.

And anyway, it's not so much a question of why would is used instead of will, but a question of why intervenes is used instead of intervened, because another common pattern (second conditional) is

If the Fed intervened, it would be an eleventh-hour bailout ...

But at this point in time, the intervention of the Fed is imminent, so the "unreal" condition if the Fed intervened must have seemed inappropriate to the writer, so he used the "real" condition if the Fed intervenes, leaving the main clause as is, with would.

Others may have different interpretations. 

CJ 

 

 

 

Some uses:

• Would functions as a more formal and more polite alternative to will.
• Would can refer to typical habitual actions and events in the past and often occurs in narratives:
• Would rather and would sooner are used to talk about preference and/or alternatives.
• Would versus Should: Should occurs as a more formal alternative to would with first person subjects in hypothetical clauses, in future-in-the-past clauses and in clauses where would can occur as a softener or hedge.
• Would can function as the past tense in reported clauses.
• Would can refer to future-in-the past when the speaker looks forward from a point in the past.
• Volition: Would may be used to refer to volition in past time situations.
• Responding: Would (especially the negative wouldn’t) can refer in past time contexts to how inanimate things responded or failed to respond to human intervention.
• Conditional sentences: Would is common in the main clause of hypothetical conditional sentences.
• Hedging: Would is often used with verbs such as advise, imagine, recommend, say, suggest, think as a softener or hedge.
• Requests: Would is frequent in requests. It is a more polite or indirect form of will.