How would you, in spanish, say "I'm done" or "I'm finished"?
If by these, you want to say that you have done a work and have finished it, in this case, you are incorrect in saying "I 'm done / I 'm finishd". the correct form is " I have done / I have finished".
for such situation, in spanish, you can use "acaber hacer algo" or "terminar hacer algo". for example:
he terminado/ he acabado = I have done/finished. like in: he terminado/ he acabado escribir la carta = I have done/finished writing the letter.
Just a side note, when something is "over" you say, "¡Ya estuvo! A funny way of saying it is ¡"Ya estufas!"
In what context would you like to say "I'm done" or "I'm finished"? There are lots of different ways those words can be used in English and unless we know the situation you want to use it in, we can't really give you an accurate translation.
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