Answer:
1. Rafael no era muy grande.
2. Estuvo nublado ayer.
3. Nosotros empezamos a las diez en punto.
4. Yo me duchaba cuando sonó el teléfono.
5. Yo empecé a las diez en punto.
6. Yo era gorda.
7. Nosotros frecuentemente íbamos al cine.
8. Tú eras bajo.
9. Todo derecho is not followed by "de"
10. Carlos va todo derecho por la calle.
11. La chica estaba entre su padre y su primo en la foto.
12. Yo doblo a la derecha en la esquina.
13. El supermercado no está a la derecha de la tienda. Esta a la izquierda de la tienda.
14. El carro está en frente de la tienda.
15. If and adjective ends in an "o", you change it to an "a" before adding the adverbial ending.
16. Seriamente - Cuidadosamente- Realmente- Contento doesn't have an adverb, although some use "contentamente" - Lentamente
Explanation:
This is a long exercise where there are different things to take into consideration. In many of the sentences you have to choose between the preterite or imperfect. In this case it's important to note if the action is in a specific moment in the past, and if it begins and ends. In that case you should use the preterite. But if the action takes place while other things take place, or if it's something that has some continuity, you should use the imperfect. The expression in English "used to" is always translated into the imperfect in Spanish.
Regarding adverbs, note that a lot of them end with "mente". But there're other types of adverbs as well. "Contentamente" is actually wrong but you can find it is used in some contexts. Contento is an adjective that doesn't really have an adverb.
