Final answer:
To rewrite the sentences using double object pronouns, we replace the single object pronouns with the appropriate combination of object pronouns. For example, in sentence 1, 'les' is the indirect object pronoun and 'las' is the direct object pronoun.
Step-by-step explanation:
1 Yo se las envié.
2 Celia les la compró.
3 Ángel me lo recomendó.
4 El mesero te lo sirvió.
5 Ella le lo pidió a la mesera.
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