Fred says he's determined to repay Ole Gunnar Solskjaer this season.
The 52m from last summer endured an underwhelming debut campaign and was linked with a move to Galatasaray.
He then missed the start of preseason due to his wedding, but Solskjaer was understanding about the situation.
"I'm really happy to have got married and, thanks to Manchester United, I was able to get my whole family together with my wife on the day," Fred told Inside United. "That was a really important day for me, for all of us, and I'm very happy.
"I had a chat with Mr Ole and he was cool for being so understanding. He was really attentive to my needs and I was allowed to come out of training to go on and get married. I did end up joining the team a bit late [on tour], but I was already training beforehand, so I'm in shape."
He added: "My first season was a bit difficult. The first year is always a little bit difficult, a year of adaptation, and, moreover, we had a season that wasn't too strong in terms of the Premier League.
"But now I'm more used to the league and I've been working hard. I've talked to the manager and backroom staff, and this season is going to be better than last season. I'm sure it is going to be very successful."
