This is the 5943rd most frequent Russian word.
свадьбу
Wedding.
Here, 'свадьбу' is in the accusative case, functioning as the direct object of the verb 'провести' (to hold).
Они решили провести свадьбу летом.
They decided to hold the wedding in the summer.
Here, 'свадьбу' is in the accusative case, showing the direction of the action 'приглашены' (invited to).
Мы были приглашены на свадьбу друга.
We were invited to a friend's wedding.
Here, 'свадьбу' is in the accusative case, indicating movement towards the event or place.