Original sentence: The perpetrator of the Winnenden school massacre was 17-year-old Timothy Kretschmer (26 July 1991 – 11 March 2009), a resident of the neighbouring municipality of Leutenbach, and graduated from Albertville Realschule in 2008 with relatively poor grades
Edited sentence: The perpetrator of the Winnenden school massacre was 17-year-old Tim Kretschmer (26 July 1991 – 11 March 2009), a resident of the neighbouring municipality of Leutenbach, and graduated from Albertville Realschule in 2008 with relatively poor grades