“Por” is used to explain the cause or motive of something
“Para” is used to refer to the purpose of an action
Answer:
9. fuimos
10. Nos sentamos
11. hacía
12. pusimos
13. esperábamos
14. vimos
15. corrió
16. tenía
17. me levanté
18. corrí
19. dejó
20. salió
Explanation:
Both the preterite and imperfect tenses are forms of the past tense, but when telling a story, background information is given in the imperfect and sudden, one-time events are talked about with the preterite. Another quick example of these two tenses used in the same sentences is:
Mi mamá estaba hablando por teléfono cuando llegó la abuela.
Mi mom was talking on the phone when my grandma arrived.
