⇒ Some Spanish verbs, such as conocer, have different meanings depending on whether they are in the past tense (el pretérito) or the imperfect tense (el imperfecto).

⇒ Some Spanish verbs have different meanings depending on whether they are perfective or imperfective.

• Perfective is just a fancy way of saying that a verb describes an action that is considered complete at or by a certain time. Put another way, the perfective aspect is used in tenses that describe singular events that occur (initiate and/or terminate) at the temporal reference point in the sentence. These tenses include the preterite tense and all perfect tenses.
• Imperfective is just an equally fancy way of saying that a verb describes an action that is considered incomplete or ongoing in the time referenced in the sentence. Tenses in the imperfective aspect describe events that are ongoing or habitual in relation to the temporal reference point. These tenses include the simple present tense, the imperfect tense, progressive tenses, the conditional tense, and the future tense.

⇒ When it comes down to it, the inherent meaning of the verb (from the perspective of a Spanish speaker) does not change with a change in aspect.

⇒ Instead what is effected is the durative nature of the event being described.

⇒ This difference comes up a lot when looking at differences between the preterite and and imperfect tenses. Let's take a look!

⇒ Here is a list of verbs that change meaning according to the perfective/imperfective relationship described above.

⇒ Now, let's take a closer look at examples of a few of the above verbs in the different tenses mentioned earlier.