Spanish pronouns le / les become se when used with lo, la, los, las (indirect with direct pronouns)

Learn about le and les becoming se in Spanish

When there is an indirect pronoun in a sentence we use: me, te, le, nos, os, les. However when the indirect pronouns le and les (meaning to him / to her / to them) are accompanied by the direct pronoun lo, la, los or las (meaning it / them) then le and les become se to avoid a clumsy sounding le lo, le la, les los etc, which is tricky to pronounce. Listen to this example:

Listen to these examples:

Note that se and the direct object pronoun have a different position depending on the verbal structure.

With a conjugated verb, se and the direct object pronoun are separate from the verb and in front.

With an infinitive, imperative or present participle, se and the direct object pronoun can be either at the end of the verbal structure and attached to the infinitive, imperative or the present participle forming a longer word:

or se and the direct object pronoun can be placed in front of the whole verbal structure, but never between the conjugated verb and the present participle or infinitive. Here are some examples to show the two possibilities, equally correct and same meaning:

Here are some more examples:

See also:
Using lo, la, los, las = him, her, it, them (direct object pronouns)

Using le and les = [to] it,him, her, them (indirect object pronouns)  

Position of Spanish direct and indirect object pronouns with infinitive/present participle and affirmative commands