Simplify the following text for a Grade 12 native English-speaking person.
Original: McCartney provided the middle section of the song , a short piano piece he had been working on independently , with lyrics about a commuter whose uneventful morning routine leads him to drift off into a dream , in addition to the `` I 'd love to turn you on . ''
Simplified: McCartney provided the fourth verse of the song , a short piano piece he had been working on by himself , with lyrics about a commuter whose uneventful morning routine leads him to drift off into a dream .