Podría / Podía / Pude

Podría / Podía / Pude
 

Many times, I can’t get a feel for which form of the verb “poder” to use when I want to convey that "I could have" done something. Does the conjugation of the verb “poder” convey different meanings?

Allow me to start with these two examples first:

I could have done it yesterday (because I had sufficient time and I was willing to do it)

Podría haberlo hecho ayer
Podía haberlo hecho ayer
Pude haberlo hecho ayer

I could have done it yesterday (I was able to do it because I finally felt well enough yesterday to do it)

Podría haberlo hecho ayer
Podía haberlo hecho ayer
Pude haberlo hecho ayer

Any and all input to help me understand which form of the verb to use is appreciated.

The preterite tense differs from all of the other tenses because it always focuses on a single event or on a specific number of discrete events. In the case of "poder", "pude" implies trying and succeeding, while "no pude" implies trying and failing.

By comparison, the imperfect focuses on actions or states without regard to their beginning or end. In the case of "poder", "podía" implies that circumstances made it possible, while "no podía" implies that circumstances made it impossible.

Thank you, wrholt.

If I understand what you are saying, I need to chose between podía and podría because pude is not an option.

Is there a difference in translation/meaning between podía and podría?

As I understand it, sometimes one of them is possible and the other one is not.

Using your examples, "(yo) podía haberlo hecho ayer" says only that you had the capacity/ability to do it yesterday. By itself it doesn't imply anything about whether or not you did it.

However, in some contexts "(yo) podría haberlo hecho ayer" implies that you did not do it in spite of the fact that you could have done it.

One example is "(yo) podría haberlo hecho ayer si me hubieras dicho que era necesario hacerlo" = "I could have done it yesterday (OR I would have been able to do it yesterday) if you had told me that it was necessary to do it." In this sentence you can't use "podía" in place of "podría".

Thanks, wrholt. Your explanations help clear that up.