The personal "a"
I am a little confused about when to use the personal "a", which has no equivalent structure in English. I believe one would use it when you have the subject of the sentence is a person, and they direct object is also a person. But I am not sure, and also I don't know if it is used in other ways. If someone could help me or point me to some grammar (I looked here and didn't find it), I would be most grateful. Thank you, Rolest
7 Answers
Escucho a Paco - I am listening to Paco
Escucho a él - I am listening to him.
Escucho a mi hermano - I am listening to my brother
Escucho a mi perro - I am listening to my dog
This is correct, except for the fact that "Escucho a él" must be "Lo escucho (a él)", with the "a él" being optional.
The rule is this:
Whenever a tonic pronoun is used (yo, tú, él, ella, Ud., nosotros, vosotros, Uds.) as the direct/indirect object, the corresponding atonic pronoun (me, te, lo, la, nos, os, los, las OR me, te, le, nos, vos, les) must also be used.
Escucho a Paco - I am listening to Paco
Escucho a él - I am listening to him.
In the first example, there is no tonic pronoun used, so it is fine the way it is. In the second, the tonic pronoun "él" is used, so the corresponding direct object pronoun "lo" must be used.
As I said, this also works with indirect object pronouns. To simply say, "I gave the book to her" you would say "Le di el libro (a ella)." Because the indirect object is a tonic pronoun, the corresponding indirect object pronoun "le" must be used, and the "a ella" is purely optional. Of course, in this case, it would probably be needed to clarify who the "le" is referring to, as "le" can mean "to him/her/you (formal)".
Anyway, to say something like "I gave the book to Rosa", it is completely and grammatically correct to simply say "Di el libro a Rosa", without even using the indirect object pronoun, since "Rosa" is not a tonic pronoun. It is more common to say "Le di el libro a Rosa", with "le" acting as an anticipatory pronoun to alert the reader to the fact that an indirect object is coming later in the sentence. Both options are equally correct, but the second provides a certain nuance.
I know all of this kind of strays from the original question, but I saw it as a great teaching moment. I'm sorry for the length. 
The personal "a" is used any time before a person's name.
Just to avoid any confusion, this statement is true but incomplete. The personal a precedes any direct object that is a person whether named or not (and is also used when the direct object is a beloved pet). For example:
Escucho a Paco - I am listening to Paco
Escucho a él - I am listening to him.
Escucho a mi hermano - I am listening to my brother
Escucho a mi perro - I am listening to my dog
Hi Rolest,
You got it half right. The personal a is used to introduce a direct object that is a person but it is not necessary that the subject of the sentence be a person, too. I hope this helped.
Try looking under prepositions in the reference section Spanishdict reference section: Prepositions You could also try this link: Personal a
Yes, you are correct that a personal a is used before a direct object that refers to a person. The subject of the sentence may or may not be a person, but if the d.o. is a person, you need the personal a.
(I'm trying to think of an example in which the subject would not be a living thing...Nothing is coming to mind, other than personification of an inanimate object, such as in a children's story...maybe it's time to go to sleep!)
Anyway, some examples are: I know the boy - Conozco al chico. She sees her friends. Ella ve a sus amigas. They love their little brother. Ellos quieren a su hermanito. I take your dog in the car. Llevo a tu perro en el coche. (pets also take the personal a).
I'm sorry I can't point you to the proper spot on this site; I'm sure there is one, and someone will come along and help you in that regard. Hopefully I have at least temporarily answered your question.
Perhaps this free ebook with help. It covers many uses of the Spanish 'a', including the so-called 'personal a'.
(I'm trying to think of an example in which the subject would not be a living thing...Nothing is coming to mind, other than personification of an inanimate object, such as in a children's story...maybe it's time to go to sleep!)
Las aguas del río los llevaron a todos.
The personal "a" is used any time before a person's name.
