By now, you probably know all about Miley Cyrus’ feud with Sinead O’Connor, but are you aware of the burgeoning vendetta between Miley Cyrus and beloved indie pop singer Sufjan Stevens?

Though Stevens is usually known for signing banjo ballads about the 50 states, Chicago landmarks and Jesus Christ, the indie singer dropped one of the harshest disses of all time on Monday: He corrected Miley Cyrus’ grammar.

In an open letter on his Tumblr (which has been temporarily renamed “The World Is Miley”), Stevens heaps loads of praise on Cyrus’ latest single “#GetItRight,” but notes that she used the wrong form of the verb “lying.” For a songwriter as precious and twee as Stevens, this is roughly the equivalent of Biggie’s Tupac diss track “Who Shot Ya?”

Dear Miley. I can’t stop listening to #GetItRight (great song, great message, great body), but maybe you need a quick grammar lesson. One particular line causes concern: “I been laying in this bed all night long.” Miley, technically speaking, you’ve been LYING, not LAYING, an irregular verb form that should only be used when there’s an object, i.e. “I been laying my tired booty on this bed all night long.” Whatever. I’m not the best lyricist, but you know what I mean. #Get It Right The Next Time. But don’t worry, even Faulkner messed it up. We all make mistakes, and surely this isn’t your worst misdemeanor.

But he didn’t stop there. Not only did Stevens call out Miley’s incorrect use of the word “laying,” but he also blasts her improper tense as well. The man is relentless in his criticism.

But also, Miley, did you know the tense here is also totally wrong. Surely you’ve heard of Present Perfect Continuous Tense (I HAVE BEEN LYING in this bed all night long [hopefully getting some beauty sleep?]) It’s a weird, equivocal, almost purgatorial tense, not quite present, not quite past, not quite here, not quite there. Somewhere in between. I feel that way all the time. It kind of sucks. But I have a feeling your “present perfect continuous” involves a lot more excitement than mine. Anyway, doesn’t that also sum up your career right now? Present. Perfect. Continuous. And Tense. Intense? Girl, you work it like Mike Tyson.

In the conclusion of his open letter, Stevens grants some praise to Cyrus, but also kind of sort of insinuates that her fame is fleeting and will soon extinguish like a candle burned down to its end. Again, this guy is pretty subtle with his insults.

Miley, I love you because you’re the Queen, grammatically and anatomically speaking. And you’re the hottest cake in the pan. Don’t ever grow old. Live brightly before your fire fades into total darkness. XXOO Sufjan

And, because the Internet is a never-ending oroboros of self-reference, a Vice copy editor has gone on to herself correct Stevens’ grammar in his letter to Miley Cyrus. Only read it if you’re craving a ridiculously pedantic-meta experience.

Listen to Miley Cyrus' offending hit "#GetItRight" and see if you can spot any additional errors below.