Having games like;
Tottenham Hotspur against Manchester City and Aston Villa against Manchester City is reason enough why nobody should write off Manchester United from qualifying for that top four position.
You should also notice that Man United will also be playing against tough opponents like Liverpool and Arsenal, but with their current disposition, they might trip on much easier teams.
I think Aston Villa is probably already beyond United's reach, but, luckily, if the below source is correct, they only need to get to 5th place to play in the UCL next season:
ps. why do we have 2 EPL threads?