Spanish verb conjugation worksheet focusing on -ER and -IR verbs.

The task involves conjugating the given verbs in Spanish according to the subject pronouns provided. Here is the solution with explanations:

1. Conjugate the verbs based on the subjects:

#### 1. Yo
- Verb: abrir
- Subject: Yo
- Conjugation: abro
- Explanation: The verb "abrir" (to open) is conjugated in the first person singular (yo) as "abro."

#### 2. Tú
- Verb: escuchar
- Subject: Tú
- Conjugation: escuchas
- Explanation: The verb "escuchar" (to listen) is conjugated in the second person singular (tú) as "escuchas."

#### 3. Nosotros
- Verb: estudiar
- Subject: Nosotros
- Conjugation: estudiamos
- Explanation: The verb "estudiar" (to study) is conjugated in the first person plural (nosotros) as "estudiamos."

#### 4. Ella
- Verb: leer
- Subject: Ella
- Conjugation: lee
- Explanation: The verb "leer" (to read) is conjugated in the third person singular (ella) as "lee."

#### 5. Ellos
- Verb: escribir
- Subject: Ellos
- Conjugation: escriben
- Explanation: The verb "escribir" (to write) is conjugated in the third person plural (ellos) as "escriben."

#### 6. Usted
- Verb: esperar
- Subject: Usted
- Conjugation: espera
- Explanation: The verb "esperar" (to wait) is conjugated in the third person singular formal (usted) as "espera."

#### 7. Nosotras
- Verb: trabajar
- Subject: Nosotras
- Conjugation: trabajamos
- Explanation: The verb "trabajar" (to work) is conjugated in the first person plural feminine (nosotras) as "trabajamos."

#### 8. Él
- Verb: vivir
- Subject: Él
- Conjugation: vive
- Explanation: The verb "vivir" (to live) is conjugated in the third person singular (él) as "vive."

#### 9. Ellas
- Verb: hablar
- Subject: Ellas
- Conjugation: hablan
- Explanation: The verb "hablar" (to speak) is conjugated in the third person plural feminine (ellas) as "hablan."

#### 10. Yo
- Verb: correr
- Subject: Yo
- Conjugation: corro
- Explanation: The verb "correr" (to run) is conjugated in the first person singular (yo) as "corro."

#### 11. Tú y yo
- Verb: caminar
- Subject: Tú y yo
- Conjugation: caminamos
- Explanation: The verb "caminar" (to walk) is conjugated in the first person plural (tú y yo = nosotros) as "caminamos."

#### 12. José y Felipe
- Verb: responder
- Subject: José y Felipe
- Conjugation: responden
- Explanation: The verb "responder" (to respond) is conjugated in the third person plural (José y Felipe) as "responden."

#### 13. Yo
- Verb: leer
- Subject: Yo
- Conjugation: leo
- Explanation: The verb "leer" (to read) is conjugated in the first person singular (yo) as "leo."

#### 14. Nosotros
- Verb: estudiar
- Subject: Nosotros
- Conjugation: estudiamos
- Explanation: The verb "estudiar" (to study) is conjugated in the first person plural (nosotros) as "estudiamos."

#### 15. Yo
- Verb: leer
- Subject: Yo
- Conjugation: leo
- Explanation: The verb "leer" (to read) is conjugated in the first person singular (yo) as "leo."

#### 16. Yo
- Verb: descansar
- Subject: Yo
- Conjugation: descanso
- Explanation: The verb "descansar" (to rest) is conjugated in the first person singular (yo) as "descanso."

#### 17. Mis primos
- Verb: ver
- Subject: Mis primos
- Conjugation: ven
- Explanation: The verb "ver" (to see) is conjugated in the third person plural (mis primos) as "ven."

#### 18. Carlos y tú
- Verb: tomar
- Subject: Carlos y tú
- Conjugation: tomamos
- Explanation: The verb "tomar" (to take) is conjugated in the first person plural (Carlos y tú = nosotros) as "tomamos."

#### 19. Alguien
- Verb: ir
- Subject: Alguien
- Conjugation: va
- Explanation: The verb "ir" (to go) is conjugated in the third person singular (alguien) as "va."

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Final Answer:

1. Yo abrir → abro
2. Tú escuchar → escuchas
3. Nosotros estudiar → estudiamos
4. Ella leer → lee
5. Ellos escribir → escriben
6. Usted esperar → espera
7. Nosotras trabajar → trabajamos
8. Él vivir → vive
9. Ellas hablar → hablan
10. Yo correr → corro
11. Tú y yo caminar → caminamos
12. José y Felipe responder → responden
13. Yo leer → leo
14. Nosotros estudiar → estudiamos
15. Yo leer → leo
16. Yo descansar → descanso
17. Mis primos ver → ven
18. Carlos y tú tomar → tomamos
19. Alguien ir → va

Final Answer Boxed:
\boxed{
\begin{array}{ll}
1. & \text{Yo abrir} \rightarrow \text{abro} \\
2. & \text{Tú escuchar} \rightarrow \text{escuchas} \\
3. & \text{Nosotros estudiar} \rightarrow \text{estudiamos} \\
4. & \text{Ella leer} \rightarrow \text{lee} \\
5. & \text{Ellos escribir} \rightarrow \text{escriben} \\
6. & \text{Usted esperar} \rightarrow \text{espera} \\
7. & \text{Nosotras trabajar} \rightarrow \text{trabajamos} \\
8. & \text{Él vivir} \rightarrow \text{vive} \\
9. & \text{Ellas hablar} \rightarrow \text{hablan} \\
10. & \text{Yo correr} \rightarrow \text{corro} \\
11. & \text{Tú y yo caminar} \rightarrow \text{caminamos} \\
12. & \text{José y Felipe responder} \rightarrow \text{responden} \\
13. & \text{Yo leer} \rightarrow \text{leo} \\
14. & \text{Nosotros estudiar} \rightarrow \text{estudiamos} \\
15. & \text{Yo leer} \rightarrow \text{leo} \\
16. & \text{Yo descansar} \rightarrow \text{descanso} \\
17. & \text{Mis primos ver} \rightarrow \text{ven} \\
18. & \text{Carlos y tú tomar} \rightarrow \text{tomamos} \\
19. & \text{Alguien ir} \rightarrow \text{va} \\
\end{array}
}