could have or would have

[Edduardo]

Hi,
when we talk about probability in the past, should I use could or would in these sentences? Can I use both?

It is doubtful that the outcome could/would have been worse.
It is unlikely that they could/would have accepted the offer.
It is likely that he could/would have gone out the window.
It is quite possible that we could/would have won this match.

Thanks.

 

[Tarheel]

Hi,
when we talk about probability in the past, should I use could or would in these sentences? Can I use EITHER?

It is doubtful that the outcome COULD have been worse.
It is unlikely that they WOULD have accepted the offer.
It is likely that he could/would have gone out the window.
It is quite possible that we could/would have won this match.

[.....]

Either is possible in the third and fourth one.

 

[jutfrank]

I think you're going to need to contextualise these sentences in order to have any hope of understanding how the modals may be working.

 

[emsr2d2]

Hi.
When we talking about probability in the past, should I use "could" or "would" in these sentences? Can I use both either?

It is doubtful that the outcome could/would have been worse.
It is unlikely that they could/would have accepted the offer.
It is likely that he could/would have gone out the window.
It is quite possible that we could/would have won this match.

Thanks.

Note my corrections above. All four sentences are grammatically possible. As jutfrank said, in order for us to comment on the appropriateness of each, we'd need to know the context.

 

[Edduardo]

I don't have more context for these sentences because they are translations from the preterite pluperfect subjunctive in Spanish, which work fine as they are, but in Spanish.

 

[Tarheel]

I don't have more context for these sentences because they are translations from the preterite pluperfect subjunctive in Spanish, which work fine as they are, but in Spanish.

I guarantee you that only 1% of native speakers know what that means.

I guess speakers of Spanish talk about grammar more than speakers of English do. Most native speakers can't tell what subjunctive means. When you add "preterite pluperfect" to it that reduces the number.

 

[5jj]

the preterite pluperfect subjunctive

There is no such tense.