мы были бы признательны если бы вы

мы были бы признательны если бы вы сообщили нам заранее планируете ли вы принимать участие в этом мероприятии.

Results (English) 1:

We would be grateful if you would have told us in advance whether you plan to participate in this event.

Results (English) 2:

we would be grateful if you would let us know in advance whether you plan to participate in this event.

Results (English) 3:

we would be grateful if you informed us in advance if you were planning to take part in this event.