Rule reminder
Full review: mi (to me), ti (to you), gli (to him/them), le (to her), ci (to us), vi (to you all). Position: before conjugated verb or attached to infinitive. Special verbs: piacere, mancare, servire, bastare, sembrare, dispiacere, credere use indirect pronouns.
Il professore …__ ha spiegato tutto con molta chiarezza. (to us)