Indirect object pronouns and placement choice
Remember that indirect objects answer the questions "To whom?" and "For whom?" For example: I write to you. Question: To whom do I write? Answer: To you. Therefore, you is the indirect object. In Spanish, whenever you have an indirect object in a sentence, you must also have the indirect object pronoun.
The indirect object pronouns are as follows:
Placement of pronouns: Indirect object pronouns work exactly as reflexive pronouns and direct object pronouns. They always come in front of a single-word conjugated verb and in front of the perfect tenses. Example:
Example: Carlos me habla por teléfono= Carlos speaks to me on the phone.
Carlos me ha hablado= Carlos has spoken to me.
When you have certain two- or three-word verbs such as infinitive constructions and progressive tenses, you may put the pronoun either at the beginning of the construction or at the end of it. You may NOT split the construction. For example, "Voy a escribir a Pablo" could be restated as "Le voy a escribir" or "Voy a escribirle".
In the exercise that follows rewrite the sentences. Move the pronoun to the other option. DO NOT SPLIT the infinitive or progressive construction.