Hey! I looked it up and it is the future subjunctive term of "ir", in the first or third person. And places a possibility in the future: to present a fact that will may be carried out in the future... or not, as "(only) over my dead body" expresses. The preposition "se" means "if" and accompagnies this tense. Literally: "Only if he/she/it would go/leave via the top of my dead body!".
Hope this helped you! I am learning as well :)
I found this website helpful by the way: http://www.learn-portuguese-with-rafa.com/future-subjunctive.html
Actually the verb to be is the first and major place where the subjunctive shows up in English. We say, as you suggested, Only if it were over my dead body. We say Only if I were rich, which is not a good conjugation in the indicative, but you say Only if I worked there or Only if I get to it, or Only if she wants to. Those look very much indicative, but they are also subjunctive. It is the hidden English subjunctive.
If it's Shakespeare it has come through changes that make it almost unrecognizable. The phrase lacks the cadence and flow of the speech of that era, especially Shakespeare. Most idioms have wide translatability, though you can make some bad errors along the way. Some of it has to do with the nature of the human condition, but I suspect it is mostly just when a phrase has the desired impact, it gets translated. Since linguistic research relies heavily on the written record it is hard to trace the origins of things like this since they often existed for a while before they were written down.
I don't think that's quite it. For one thing , a conditional is a clause with the word would in it, or , in the case of Portuguese, a verb with -ia, -ias, -íamos etc at the end. So that doesn't really apply here. For another, the for in this sentence is the future subjunctive of the verb ir, and it has to do with something that may happen in future. But your translation makes sense too, because no one will say Only if it is over my dead body, even though this is the way the future subjunctive is interpreted in English. We'd rather say either if it was or if it were.
You see, in English, there are 4 kinds of conditionals (check out this link over here for more info: https://www2.estrellamountain.edu/faculty/stonebrink/ESL040/4_types_of_conditionals.htm), and each one is peculiar in meaning.
What we see above is an if-clause with the Future Subjunctive form of the verb ser. It's often used with the future tense in the second part, isn't it? As in Se eu tiver dinheiro, farei uma viagem. This sentence corresponds with the First Conditional of the English language: If I have money, I will take a trip. But not If I had money, I would take a trip, because that would be the Second Conditional, which is interpreted with the help of other Subjunctive tenses in Portuguese.
I understand that literally having something done right over one's corpse can't be viewed as a realistic thing, and in a way it is, indeed, hypothetical, but the Future Subjunctive has to do with the future, and that's why it can't be translated as 'if it was over my dead body'.
Besides, according to strict grammar, the way to go is If it were over my dead body, which is one of the few cases where the Subjunctive sort of survives in English.
So, while you can say that what we see above is more or less like the English conditional, you have to add that it's only the First Conditional that's at issue here.
I can't say I have profound knowledge on either Portuguese or English grammar. Right now I'm just talking about the correspondence between the two languages, which is what you seem to get wrong.
Mate, you're neither here nor there.
I have checked your links, and it appears that you haven't even read the first one with enough attention yourself. It says at the end that you use was only when you're talking about an event that did, in fact, happen in the past, and that's not a subjunctive, that's a zero conditional. In all other cases, as is shown in the link which you've so carefully and generously provided but sadly failed to properly read into, the preferred option is were. That's what the English Subjunctive is, and that's how the verb to be functions in it.
Well, you see, the translation you gave in your first comment isn't actually l-i-t-e-r-a-l. The literal way to interpret this would be by saying 'Only if it is over my dead body', because, as I've shown above, such a construction in Portuguese corresponds with the First Conditional in English.
And yes, there is another form in which the Subjunctive exists in English, which is what the second link is about, but that's a whole 'nother story, and it's not even what's at issue here.
Well, it seems you have not checked the links I've provided...I'll write them, without using python code...
were or was? ----- Was
Subjunctive----used to express intention or proposal about the future...
I know that I cannot translate as I did on my original comment, that's why I wrote "l-i-t-e-r-a-l-l-y".(not as it should be written)..Because not even in english one should interprete idioms literally (usually)....
The number type and order of exercises is rather random. Sometimes exercises repeat. It partially depends on how many sentences are appropriate for any unit. At one point I was seeing several questions repeated each unit in my German course, although no other has been that bad.