Presente o Pretérito
Habló con la profesora
¿Qué es el pretérito?
Translation: He/She spoke with the teacher.
Explanation: While present tense has the yo ending of -o (HA-blo), an accented -ó is the él/ella/ud conjugation in the preterite (ha-BLO).
Mi amigo (seguir, sacar) las reglas.
¿Qué es seguir?
Translation: My friend followed the rules.
Explanation: Since reglas means rules, between sacar (to take out) and seguir (to follow), seguir fits the context better. Remember that seguir is a present tense stem changer (e-->i), ends in -ir, and being conjugated for 3rd person.
Hace
¿Qué es hizo?
Explanation: Hace is the present tense conjugation of hacer for él/ella/ud. In the preterite, hacer is irregular with the new stem of HIC- and the ending for él/ella/ud is -o. HOWEVER, hico creates a pronunciation error so the c is changed to z.
La chica - servir
¿Qué es sirvió?
Explanation: Servir is a present tense stem changer (e-->i), ends in -ir, and being conjugation for 3rd person, so it requires an e-->i stem change. Él/ella/ud gets an -ió ending.
Ellos - dar
¿Qué es dieron?
Explanation: Dar is completely irregular and must be memorized.
di/diste/dio/dimos/disteis/dieron
Duermo a las 10 de la noche.
¿Qué es el presente?
Translation: I sleep at 10pm.
Explanation: Dormir is a present and preterite tense stem changer. The o-->ue stem change occurs in the present tense while the preterite tense has an o-->u stem change which doesn't apply to yo conjugations.
Los estudiantes (tener, traer) sus mochilas a la clase ayer.
¿Qué es traer?
Translation: The students brought their backpacks to class yesterday.
Explanation: While you can have (tener) your backpack in class, the sentence uses the preposition TO CLASS. You can't have your backpack to class, however you can BRING it to class. Remember, traer is an irregular verb with the new stem traj-. Also take note that ellos conjugations usually end in -ieron with the exception of stems that end in "j" thus getting the ending -eron without the i.
Voy
¿Qué es fui?
Explanation: Voy is the present tense yo conjugation of ir. In the preterite, the irregular conjugation of ir for yo is fui.
Nosotros - preferir
¿Qué es preferimos?
Explanation: Preferir is a present tense stem changer (e-->ie), ends in -ir, but it's being conjugation for nosotros and not 3rd person, so no stem change. The stem prefer- is completed with the ending -imos.
Ud. - leer
¿Qué es leyó?
Explanation: Ud. is short for usted which gets the same conjugation as él/ella. The stem of leer (le-) with the usted ending (-ió) creates triple vowels which is not allowed in Spanish, so i must be changed to y.
Corrimos por las calles.
¿Qué es el preterito?
Translation: We ran through the streets.
Explanation: While generally you'd need further context to determine the tense of a nosotros sentence, for -er verbs like correr, the present tense (-emos) is different from the preterite tense (-imos).
Mis hermanas (poder, poner) el libro en la mesa.
¿Qué es poner?
Translation: My sisters put the book on the table.
Explanation: Poder means to be able to which doesn't work with the context of the sentence. Generally, a conjugation of poder is almost always accompanied by another infinitive verb which is not included in this sentence.
Duermen
¿Qué es durmieron?
Explanation: Dormir is a present tense o-->ue stem changer. The -en ending comes from ellos/ellas/uds. In the preterite, since dormir is a present tense stem changer, that ends in -ir, and being conjugated for ellos/ellas/uds, the o-->u stem change and the ending -ieron are needed.
Uds. - repetir
¿Qué es repitieron?
Explanation: Repetir is a present tense stem changer (e-->i), ends in -ir, and being conjugation for 3rd person, so it requires an e-->i stem change. Ellos/ellas/uds gets an -ieron ending. Note that it's the last "e" of the stem that changes.
El grupo - andar
¿Qué es anduvo?
Explanation: While groups are made up of multiple people, it is considered a singular entity... one group. This receives the él/ella/ud. conjugation. Andar is irregular with the new stem of anduv-. Irregular preterite él/ella/ud conjugations get the ending -o.
Estudias las matemáticas.
¿Qué es el presente?
Translation: You study math.
Explanation: The regular stem of estudiar is estudi- with the regular present tense tú ending -as.
Ellas le (pedir, venir) la cuenta del mesero.
¿Qué es pedir?
Translation: They asked for the check from the waiter.
Explanation: Venir means to come which in regards to a bill, does not make sense. You can, however, ask for (pedir) the check. Remember that pedir is a present tense stem changer (e-->i), ends in -ir, and being conjugated for 3rd person so this would require a stem change e-->i.
Sé
¿Qué es supe?
Explanation: The present tense sé is the irregular yo conjugation of saber. Saber is also irregular in the preterite. The new stem is sup- while the yo ending -e completes the conjugation.
Yo - jugar
¿Qué es jugué?
Explanation: While jugar is a present tense stem changer (u-->ue), it doesn't end in -ir, and isn't being conjugated for 3rd person. This means we keep the original stem jug-. HOWEVER, when adding the regular -ar yo ending -é, that creates a pronunciation error as it is a -gar verb. To correct this, a "u" is added.
Tú - venir
¿Qué es viniste?
Explanation: Venir is irregular in the preterite with the new stem vin- and the irregular preterite tú ending of -iste. Since it is irregular and not a stem changer, tú does get the new modified stem.
Prefirió la ensalada.
¿Qué es el pretérito?
Translation: He/She preferred the salad.
Explanation: Preferir is a stem changer in the present tense, ends in -ir, and being conjugated for él/ella/ud. It requires an e-->i stem change with the regular -ir ending of -ió.
Tú (creer, divertirse) en la fiesta.
¿Qué es divertirse?
Translation: You had fun at the party.
Explanation: Creer means to believe which doesn't work here. Take note that divertirse is reflexive and conjugating it requires the reflexive pronoun "te". Also, while divertir is a present tense stem changer (e-->ie) that ends in -ir, conjugating for tú does not call for a stem change in the preterite.
(te divertiste)
Me comunico
¿Qué es me comuniqué?
Explanation: Comunicarse in the present tense is regular. Stem (comunic-) with the yo ending (-o). The reflexive pronoun me goes before the conjugated verb. In the preterite tense, the stem (comunic) with the yo ending (-é) creates a pronunciation error as it is a -car verb. The "c" needs to change to "qu"
Ella - dormir
¿Qué es durmió?
Explanation: Dormir is a present tense stem changer (o-->ue), ends in -ir, and being conjugation for 3rd person, so it requires an o-->u stem change. Él/ella/ud gets an -ió ending. Note that while it's o-->u present tense, it becomes o-->u in the preterite.
Yo - querer
¿Qué es quise?
Explanation: Querer is irregular in the preterite with the new stem quis- and the irregular preterite yo ending is -e.