*Use the Imperfect to describe actions that are occuring in the past.
Por Ejemplo: Mientras Paco conducía, su esposa leía una revista.
While Paco was driving, his wife was reading a magazine.
*Use the Imperfect Indicative to express a habitual action. Frequently, this is equivalent to the English expression "Used To".
Por Ejemplo: Todos los años, mi familía iban a Mexico.
Every year, my famila used to go to Mexico.
Enrique cocinía la cena todos los sabados.
Andrew used to cook dinner every Saturday.
*Use the Imperfect Indicative to describe the circumstances surrounding a specific event in the past. This includes time, weather, physical state, and mental condition.
Por Ejemplo: Eran a las dos.
It was two o'clock.
Hacía calor y sol.
It was hot and sunny.
Carla se vestía en un traje de baño rojo.
Carla wore a red swimsuit.
Carla quería nadar en el lago más, pero estaba cansada.
Carla wanted to swim in the lake more, but was tired.