Preterite vs. Preterite vs. imperfectimperfectUsing both in 1 sentence

Preterite—imperfect formulas

0The preterite and imperfect tenses are often used together in the same sentence. There are a few typical sentence/structure formulas that are easy to learn. Two vocabulary words that are necessary to join two past tense verbs in the same sentence are mientras (while) and cuando (when). Notice that cuando does not have an accent mark because it is not being used as a question word.

Joining verbs with mientras0 The conjunction mientras can be used to join two verbs in

the imperfect, or it can be used in sentences where one verb is in the preterite and the other is in the imperfect. The sentence will change meaning depending on the tense of the verbs joined by mientras.

0 To indicate that two actions are occurring simultaneously and are assumed to be ongoing, the conjunction word mientras is used between two verbs, and both verbs will be conjugated in the imperfect tense. It is necessary that neither action interrupt the other for both verbs to be conjugated in the imperfect tense.

Mientras examples

0Sentence structure formula: Imperfect mientras imperfect

0Ellos secaban los platos mientras yo los lavaba.They were drying the dishes while I was washing them.

0Mientras nosotros mirábamos televisión, ellos se vestían. While we watched television, they got dressed.

0Ella leía el periódico mientras yo cocinaba. She read the newspaper while I cooked.

Interrupted actions0When the verb following mientras is in the imperfect

and the other verb is in the preterite, the action of the verb in the preterite interrupts the ongoing action of the verb in the imperfect.

0Sentence structure formula: Preterite mientras imperfect

0 Samuel llamó mientras tú estudiabas.Samuel called while you were studying.

0 It is acceptable to have mientras in between the two verbs, or mientras may begin the sentence followed by a verb in the imperfect, a comma, and a verb in the preterite.

Joining verbs with cuando

0The conjunction cuando is almost always followed by the preterite tense because it indicates the specific moment of the action of the verb that follows it. The other verb in the sentence may be an ongoing action that is interrupted by the preterite verb. In such cases, the ongoing verb is in the imperfect tense.

Cuando examples0        Sentence structure formula: Imperfect cuando

preterite0             Alicia trabajaba cuando yo entré en la oficina.

            Alicia was working when I entered the office.0 Just like sentences using mientras, the sentence order can

be switched around, but the verb following cuando will be conjugated in the preterite tense, regardless of where it is placed in the sentence.

0          Sentence structure formula: Cuando preterite, imperfect

0             Cuando yo entré en la oficina, Alicia trabajaba.            When I entered the office, Alicia was working.

Cuando with preterite0 In some sentences, the conjunction cuando is used to join two

preterite verbs. This sentence structure indicates that the action of both verbs was completed at the same time or that one was the result of the other.

0           Sentence structure formula: Preterite cuando preterite0              Carlos me llamó cuando él llegó.

             Carlos called me when he arrived.0              Yo grité cuando vi al fantasma.

             I screamed when I saw the ghost.0 Sometimes the same basic construction is reversed. Whenever

the conjunction cuando is the first word of the sentence, a comma is placed between the two preterite verbs.

0           Sentence structure formula: Cuando preterite, preterite0              Cuando él llegó, Carlos me llamó

             When he arrived, Carlos called me.0             Cuando vi al fantasma, yo grité.

            When I saw the ghost, I screamed.