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1. yo / almorzar
The verb "almorzar" means to eat/have lunch. It also is a stem-changing verb. This means that the "o" changes to "ue" only when the subject is yo, tú, él, ella, ellos or ellas. This never occurs in the nosotros/vosotros subject.
Answer: Yo / almuerzo
2. tú / cerrar
The verb "cerrar" means to close, and it is also a stem-changing verb. In this case, the "e" changes to "ie". Since the subject is "tú", the stem-change occurs.
Answer: Tú / cierras
3. nosotros / pensar
The verb "pensar" means to think, and is also a stem-changing verb. The "e" changes to "ie", but the subject is nosotros, so there is no stem-change.
Answer: Nosotros / pensamos
4. ellos / dormir
The verb "dormir" means to sleep, and it is also a stem-changing verb the like the other. The "o" is changed to "ue". Since it does not have the subject nosotros or vosotros, the stem-change occurs.
Answer: Ellos / duermen
5. yo / traer
The verb "traer" means to bring. This verb is interesting because it is a -go verb. This means that when the subject is yo, the verb ends in -go, and it also replaces the "e" with an "i".
Answer: Yo / traigo
6. nosotros / decir
The verb "decir" means to say/tell. It is also a -go verb, so the ending is replaced with -go when the subject is yo. Since the subject is nosotros, there is no special change, except the ending is changed due to the subject.
Answer: nosotros / decimos
7. él / volver
The verb volver means to return, and it is also a stem-changing verb. Like "dormir", the "o" is changed to "ue" when the subject is yo, tú, él, ella, ellos, or ellas.
Answer: Él / vuelve
8. yo / venir
The verb "venir" means to come, and is also a -go verb in the subject yo.
Answer: Yo / vengo
9. ella / perder
The verb "perder" means to lose, and is a stem-changing verb. The "e" is replaced with "ie" when the subject is yo, tú, él, ella, ellos, or ellas.
Answer: ella / pierde
10. tú / entender
The verb "entender" means to understand, and is a stem-changing verb. For this verb, the "e" is replaced with "ie", and since the subject is tú, the stem-change occurs.
Answer: Tú / entiendes
Final answers:
- Yo almuerzo
- Tú cierras
- Nosotros pensamos
- Ellos duermen
- Yo traigo
- Nosotros decimos
- Él vuelve
- Yo vengo
- Ella pierde
- Tú entiendes