Answer:
1- sabemos
2- sabes
3- saben
4- sé
5- sabe
6- sabe
7- sabemos
Explanation:
In this case, you need to provide different conjugations of the verb "saber" according to the subject of the sentence. The conjugations of "saber" in the present tense of the indicative mood are the following:
1st person singular: yo sé
2nd person singular: tú sabes
3rd person singular: él/ella/usted. sabe
2nd person plural: nosotros sabemos
3rd person plural: ellos/ustedes saben
If we take that into account, the exercise is completed as follows:
1- Sara y yo sabemos jugar al tenis. (2nd person plural nosotros)
2- ¿Por qué no sabes tú estos verbos? (2nd person singular tú)
3- Mis padres saben hablar japonés. (3rd person plural ellos)
4- Yo sé a qué hora es la clase. (1st person singular yo)
5- Usted no sabe dónde vivo. (3rd person singular usted)
6- Mi hermano no sabe nadar. (3rd person singular él)
7- Nosotros sabemos muchas cosas. (2nd person plural nosotros)