Complex sentence: The 2009 G-20 London summit protests occurred in the days around the G-20 summit on 2 April 2009, which was the focus of protests from a number of groups over various long-standing and topical issues.
Split into simpler sentences: The 2009 G20 London summit protests occurred in the days around the 2 April 2009 G20 London summit. The summit was the focus of protests from a number of groups over various long-standing and topical issues.