Simplify the following text for a Grade 11 native English-speaking person.
Original: But most of his later life was occupied in writing about Shakespeare , including : a photolithographic reproduction of the 1600 Quarto of Much Ado about Nothing in 1864 and of the First Folio of Shakespeare in 1866 ; and papers on Unsuspected Corruptions of Shakespeare 's Text , published from 1872 to his death .
Simplified: Most of his later life was spent in writing about Shakespeare , including : a photo lithographic reproduction of the 1600 Much Ado about Nothing in 1864 and of the first folio of Shakespeare in 1866 . He wrote articles on Unsuspected corruptions of Shakespeare 's text , published from 1872 to his death .