It has been an eventful year for football and Manchester United fans.
They saw the return of Portuguese forward Cristiano Ronaldo on a two-year deal, and witnessed embattled manager Ole Gunnar Solskjaer sacked after a string of poor results. There was also the pain of a Europa League final defeat.
But there is still hope. United have moved into the round of 16 in the Champions League and have a decent shot at top four finish in the league.
With so much happening during an intense year at Old Trafford, let's jog your memories one more time.
Below is the Manchester United quiz for 2021. Test your knowledge about all things United and see if you can get top marks.