The 25-year-old was signed by manager Louis van Gaal for £12.7million from Torino in the summer and he has featured in all but one league games for United this season.
He said: "In England, the new experience started in the best possible way and I hope it can continue like this.
"Playing in another league in another country helps you to grow in every way.
"In the Premier League it is more physical and less tactical than Serie A. Compared to Italy, there is less attention to nutrition."