We wouldn't be going

[ROBINDESBOIS]

we wouldn't be going

what ´s the use of that tense?

[poli]

We wouldn't be going if we knew you were ill
We wouldn't go if we knew you were ill.

The difference is subtle, and the meanings are somewhat interchangeable, but wouldn't be going is progressive, and implies the active preparation of going.

[ROBINDESBOIS]

I HAD TO DANCE but Ibroke my leg so I wouldn't be dancing after all ???

I can't really get the meaning

[poli]

I HAD TO DANCE but Ibroke my leg so I wouldn't be dancing after all ???

I can't really get the meaning Here's a direct translation.

Tuviera que bailar pero quebré mi pierna, y por eso no estaría bailando (por eso no bailaría) en todas maneras.