The melody of I Knew You Were Trouble by Taylor Swift runs 502 notes across 67 bars, 3:06 long in G at 150 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? I Knew You Were Trouble chords and lyrics.