I explain to you, in the Spanish language as in the English language there are irregular verbs. Which means that the <u>morpheme</u> changes depending on many things.
In this case, the irregular verb is in the past indefinite form. In the first column there are two irregular verbs <u>WITHOUT conjugation</u>.

In the third column I think you should translate the verb into English.
- Ir ⇝ <u>To go</u>
- Hacer ⇝ <u>To do</u>
- Llevar ⇝ <u>To wear</u>
Answer:
plural: La clases, una horas, Los cuadernos
singular: amigo, una estudiante, una escuela
Explanation: