6. This sentence is indicative; the direct object pronoun (lo) must come after the subject and before the verb.
Answer: Te lo doy.
7. Same as above, the direct object pronoun (la this time) comes before the verb.
Answer: Se la compra.
8. This sentence is in the imperative mood; the parts of the sentence will go action + subject + object.
Answer: ¡Dimelo!
9. This question is asking which sentence is in passive voice. The sentences are: 1) the book was written by Cervantes, 2) Cervantes wrote the book, 3) the book wrote Cervantes. Passive voice is when the subject is acted on by the verb.
Answer: El libro fue escrito por Cervantes.