Learn Italian: Tutti noi eravamo presenti alla riunione. - All of us were present at the meeting.

In Italian, when the quantifier tutto is used with a stressed (tonic) pronoun like noi, voi, or loro, you do not use a preposition like "of" (di). You simply place tutti directly before the pronoun: tutti noi (all of us), tutti voi (all of you), tutti loro (all of them).

Does the form of "tutto" always have to match the pronoun?

Yes. Because noi refers to a group of people, the quantifier takes its masculine plural form, tutti. If the speaker is female and referring to a group made up entirely of women, she would say tutte noi.

Could I put "tutti" after the verb, like "Noi eravamo tutti presenti"?

Yes, that is also perfectly natural! You can separate them and say Noi eravamo tutti presenti or simply Eravamo tutti presenti (dropping the subject pronoun noi altogether). Keeping tutti noi together at the start of the sentence just places a slightly stronger emphasis on the "All of us" aspect.

Why use the imperfect tense "eravamo" here instead of the passato prossimo "siamo stati"?

The imperfect (eravamo) is used here to describe a state of being or to set a scene in the past. It focuses on the ongoing fact that the group was in attendance at that moment in time, rather than a completed, standalone event.