When two object pronouns are used together, the indirect always precedes the direct. If meaning still remains unclear, the mnemonic device I-D (indirect, direct) may be helpful in remembering their order.
|Pablo nos las dice.||Pablo tells them to us (tells us them).|
|Mi hermano me lo contó.||My brother told it to me.|
Of the three types of non-prepositional object pronouns (reflexive, indirect, direct), although all three are never present in the same clause, their order is reflexive, indirect, direct (mnemonic device: R-I-D):
|Guillermo se las bebió.||Guillermo drank them up.|
When Spanish finds two object pronouns in the third person, the indirect (the first one) changes to se. If the context is not clear, a prepositional phrase clarifies the meaning of the indirect object, If, for example, the meaning of Se la digo is not apparent in context, any of the following prepositional phrases can be added to clarify the meaning of the se: a Ud, a él, a ella, a Uds., a ellos, a ellas.
The two object pronouns are never separated (unless there are two verbs and one pronoun clearly refers to one verb, while the other does to another, eg., Me ayuda a comprenderlo [“He helps me to understand it”]). If an infinitive or present participle is present, the pronouns either precede the conjugated verb or are attached to either of the former.
|Va a dármelo.||He’s going to give it to me.|
|Me lo va a dar.||He’s going to give it to me.|
|Está diciéndomelo.||She’s telling it to me.|
|Me lo está diciendo.||She’s telling it to me.|
In written Spanish, there is a slight preference that the pronouns be attached to the infinitive (or present participle).