Answer:
La profesora nos exige que estudiemos una hora cada noche.
Step-by-step explanation:
''Exige'' is in the Spanish simple present tense and ''exigió'' in the preterite tense. The simple present tense is used to talk about habitual situations, routines, universal truths, facts and things happening now or in the near future. If it says ''cada noche'', it means it is something that you do every day.