What is the difference between preterite and imperfect

Imperfect implies that the past action did not have a definite beginning or a definite end , preterite tells us specifically when an action took place .

Use of the imperfect tense implies that the past action did not have a definite beginning or a definite end. You have now learned the basic difference between the preterite and the imperfect: The preterite tells us specifically when an action took place.