Who's eating who?
Let's say I want to translate the following sentence to Spanish:
The spider ate the ant.
If I put, "La araña se la comió la hormiga." would it be correct? If so, how would one know which was doing the eating--the spider, or the ant--since the order of the nouns doesn't matter?
Would it be enough to just put the letter "a" right before the word "hormiga"?
Thanks for helping me.
5 Answers
An important point is that 'comer' is 'to eat' but 'comerse' is 'to eat (all) up' so you can use either but the meaning will be slightly different.
La araña comió a la hormiga.
The spider ate the ant.
or
La araña se comió a la hormiga.
The spider ate the ant all up.

I think it would be:
La araña le comió la hormiga.
La araña le comió la panza de la hormiga.
I could correctly say: "La mujer le tomó el café." but with animals using "le" indicates a part of and not the whole like it does with people and things.
Here are some examples I found:
La araña se comió la mosca de una mordida.
El perro se comió la tarea.
Un tiburón se comió a un surfista en Australia.
I talked with several Ticos and they said do not use the "a". Several stated it sounds bad but one explained because it is in the past. Keep in mind it is not out of a text book but from the streets of Costa Rica so it may be different in other areas.
¿La araña comió la hormiga? Without using "se" it needs to be a question.
La araña se comió la hormiga.
La araña le comió la panza de la hormiga. With animals using "le" indicates a part of and not the whole like it does with people and things.
To use the "a" write it similar to this.
La araña se va/fue a comer a la hormiga.
I will put in my answer, even though in the time it took me type it you seem to have been adequately answered, but no one addressed why "la" does not belong in your attempt.
comerse implies to eat something up, to devour it entirely, to finish it off-
comer implies to eat something in general
So for I eat apples- como manzanas
for I ate the apple- me comí la manzana.
The second part is that redundant pronouns are redundant indirect pronouns, not direct pronouns.
Le di la manzana a Juan.
I gave the apple to Juan.
Le refers to Juan because he is the indirect object, and you have to mark the indirect object in Spanish, even if it comes later. Since la manzana is a direct object, a marker is not needed for it. You do not say "se la di la manzana a Juan."