The answer for question four is: actuó.
Explanation:
actuaba is imperfect. Imperfect has the endings yo aba, tú abas, usted aba, nosotros abamos, ustedes aban
Actua is present tense usted form because of the ending “a.” The endings for present tense are yo-o, tú-as, usted-a, nosotros-amos, ustedes-an.
Actuo is present tense yo form.
The endings for preterite tense ar verbs are:
yo-é, tú-aste, usted-ó, nosotros-amos, ustedes-aron. You’re looking for the singular usted preterite form, so drop the “ar” in actuar, and add the ending ó. That’s all there is to conjugate verbs in Spanish.
