Consider this translation:
I would have jumped the rope.
Hubiese saltado a la cuerda.
Now, how would we translate the same sentence if I added "if I had to" to it?
I would have jumped the rope if I had to.
Consider this translation:
I would have jumped the rope.
Hubiese saltado a la cuerda.
Now, how would we translate the same sentence if I added "if I had to" to it?
I would have jumped the rope if I had to.
Your example is wrong to begin with.
I would have jumped the rope.
Hubiese saltado la cuerda.
Hubiese saltado la cuerda
translats to Had I jumped the rope
The correct translation would be
I would have jumped the rope.
Habría saltado la cuerda.
Here is how I would say it:
Si tuviera que saltarla, habría saltado la cuerda
Si tuviera que saltar la cuerda, la habría saltado
If you use haber, like in this sentence
Si hubiese tenido que hacerlo, habría saltado la cuerda
It will translate to:
If I had had to do it, I would have jumped the rope.
Hubiese and Hubiera are the same thing, by the way.
If you want to say, I would have done it
, you would say
Lo habría hecho
When you start writing conditional statements, with a cause, and reason.. you get sentences like this
If I had an apple, then I would eat it
Si yo tuviera una manzana la comería
It boils down to this guideline
If... something in the subjunctive.. then... something in the conditional..
or
Something in the conditional, then.. something subjunctive.
example
Yo habría saltado la cuerda si yo tuviera que hacerlo.
saltar a
, then the OP is wrong... The question was about the use of past subjunctive, but was using it incorrectly. He was using the subjunctive when he should have used the conditional tense.
It's not answering the question you posed but it's what you want to know:
Hubiese saltado la cuerda si hubiese tenido que (hacerlo).
The omission of the last verb is advanced. Or
Si hubiese tenido que hacerlo, hubiese saltado la cuerda.
Si hubiese tenido que hacerlo, hubiese saltado la cuerda.
would mean.. If I had had to do it, had jumped the rope.
The correct phrase is:
Habría saltado la cuerda si hubiera tenido que hacerlo.
Correct, but slightly clumsy. Some alternatives:
Si hubiera tenido que saltar la cuerda, lo habría hecho.
Habría saltado la cuerda en caso de haber tenido que hacerlo.
Habría saltado la cuerda de ser necesario.
Habría saltado la cuerda de haberme visto obligado a ello.
"Saltar a la cuerda" or "saltar la cuerda"? This varies by region. But that's not what you were asking about....
For clarity about hubiera, hubiese and habría, please see this excellent and concise post: https://spanish.stackexchange.com/a/20738/9385.
Now, what you were actually asking:
How would this be expressed in Spanish? "I would have jumped the rope if I had to."
I'm going to modify your question a little bit because "jumped the rope" is awkward for me to work with. First, because I would say, "I would have jump-roped" (and that might veer us off to *what exactly is the past participle of "to jump rope") and second, because it's hard for me to imagine someone being required to jump rope.
I would have gone to the bank yesterday (to make a deposit) if I had to [but it wasn't necessary because my automatic paycheck deposit came through in time].
A literal translation would be
Hubiera ido al banco ayer (para hacer un depósito) si hubiera tenido que hacerlo.
In place of the first hubiera, hubiese and habría are also possible. In place of the second, hubiese is also possible. (See the previously cited https://spanish.stackexchange.com/a/20738/9385.)
A little bit more natural would be
Habría ido al banco ayer si hubiera sido necesario.
or
Habría ido al banco ayer si hubiera tenido que hacerlo.
But the natural, idiomatic way to express this is:
Hubiera ido al banco ayer de ser necesario.
Let's back-translate, to make sure you understand what this means:
I would have gone to the bank yesterday if it had been necessary.
If I had to cook -> Si yo tuviera que cocinar.
Si tuviera que cocinar is less accurate.