Suplir por vs. suplir para

Suplir por vs. suplir para
 

A native-Spanish-speaking friend of mine was working as a substitute teacher recently. She said something about an upcoming subbing assignment.... The conversation continued something like this:

Lou Ann: ¿¡No vas a suplir el lunes por nadie!?

To which I was corrected, and told that it should be "para". :?::?::?:

I don't often have difficulty with por y para any more ... my Argentine professors really helped with that. So this surprises me, because I really thought that in this case, "por" would be the right choice because it's like an exchange ... these classes are being taught by this one teacher instead of (in exchange for) the other teacher.

As a result, I'm not at all sure why it's supposed to be "para"...... ???

Hmm... I'd say "suplir a alguien". :thinking:


Lou Ann va a suplir a María el lunes. -> Would be saying that Lou Ann will do María's work on Monday.

María va a suplir a Lou Ann por Pedro. -> Would mean to me that Pedro was supposed to originally replace Lou Ann, but María is going to do that instead.

María va a suplir a Lou Ann para Pedro. -> Doesn't make much sense to me, as it would mean that María is going to replace Lou Ann, to please Pedro (as if Pedro would want her to do that). :thinking:

I agree with Angelica.

Also:

Vas a substituir a ....?

o

Vas a servir de substituto por ...

I'll have to ask her why para and not a or por. She says suplr, always. In fact, I believe she calls herself a "suplente".....

Sí, suplir y suplente.