Ser is a stem-changing verb. To say they are and we are in Spanish, you would use: son and sois.
I'm currently learning this so I know.
the De should not be in there
Answer:
1. Teresa, José y yo firmamos la petición.
2. Yo leí el libro.
3. Yo pregunté por la salud de Jaime.
4. Yo hablo varias lenguas.
5. Yo escucho el ruido.
hopefully this helped
Explanation: