The melody of I Heard It Through The Grapevine by Marvin Gaye runs 319 notes across 32 bars, 2:16 long in Em at 120 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 Heard It Through The Grapevine chords and lyrics.