make nonsense of
make (a) nonsense of (something)
To lessen something serious or important to a silly or ridiculous level. The candidate has been making a nonsense of the whole political process, but many voters feel that that is just what's needed. I don't appreciate you making nonsense of this class with your rude remarks and obnoxious behavior.
make nonsense of something
to make something appear to be silly or nonsensical. You are just making nonsense of everything I have tried to do. Your statement makes nonsense of everything you have said before.