Answer:
1. hablaba
2. daba, interrumpió
Explanation:
1-- The action was ongoing-- Sara was speaking (hablaba) on the telephone; therefore we would use the imperfect tense.
2-- For the first part, Ana was giving (daba) a presentation. This is an ongoing action, so it is imperfect. The second part, the professor interrupted her (la interrumpió) . Because it was an action that interrupted an ongoing action, you use the preterit tense.
The general rules for preterit vs imperfect are as follows:
Preterit:
1. Use for single, past events or a specific moment in time
2. Use for a list of sequential actions. (ex: I bought a car, ate at a restaurant, and then went home to sleep/Compré un carro, comí en un restaurante, y después regresé a casa para dormir).
3. Use for actions that interrupt ongoing action.
4. Use for verbs referring to the senses (hands, feet, eyes, ears, nose, mouth)
Imperfect:
1. Action(s) in progress in the past (ex: was running)
2. Repeated, habitual actions (used to)
3. Interrupted action
4. Telling what the time, weather, or age was
5. Descriptions of physical or mental state.
