Indirect objects to pronouns

Indirect objects to pronouns
 

1. Los estudiantes traen unos los textos a las profesoras.
2. Pienso comprar a mi hermana un reloj.
3. Tengo que dar a vosotros el examen ahora.
4. El agente vende los pasajes a los turistas.

I am trying to change the indirect object to pronouns.

1. Los estudiantes les traen unos textos.
2. Le pienso comprar un reloj.
3. Os tengo que dar el examen ahora.
4. El agente les vende los pasajes.

Hopefully I didnt make many mistakes. Let me know where i went wrong.

There's nothing wrong with the indirect object pronouns you chose.

Restating the indirect object for clarification purposes in the ambiguous third person is a good idea. So, all but number 3 should still contain the indirect object ALONG WITH the indirect object pronoun.

I agree that there are no mistakes with pronouns.

Only a little remark: on the original sentence for no. 1, it should be either "unos" or "los"; they can't go together. :)