Hey there! I'm happy to help!
38. We have the word "anoche", so this mean it happened once so it is preterite. It is also using the tú form. So, we will use the tú past tense a. hiciste.
39. We have the word "cada día", which makes this something continuous, so this is most likely the imperfect tense. We also have the subject nosotros. So this is c. veíamos (víamos isn't a word).
40. This appears to be something that happened once (the girls arrived at eight), so this is preterite. It is also using the ellas form. Our answer is c. llegaron.
41. Todos los veranos is a continous past event, so this is imperfect. We are also using ella, so it is a. iba.
42. We are telling the time. Time is continuous, so we will use imperfect. It is also third person plural (time is plural), so it is c. eran.
43. We have the word ayer, which is preterite as this thing happened once. We also have nosotros (mi hermano y yo), so we will use b. jugamos.
44. Siempre is continuous, so we will use imperfect. It is also third person, so we will use c. hacía.
45. This is imperfect as it talks about a continuous event (being young) and we are using yo, so it is b. era.
46. This raining is a one time event, so it is preterite. We are using third person singular (it started), so we will use d. empezó.
47. this going to dance is a one time event, so it is preterite. We are using third person plural, so we will use b. fueron.
Have a wonderful day and keep on learning! :D