Complex sentence: Kürten did not attack again for six months, stabbing three people in separate attacks on 21 August; murdering two foster sisters, aged five and 14, two days later; and stabbing another woman on 24 August.
Split into simpler sentences: Kürten did not attack again for six months, until 21 August when he stabbed three people in separate attacks. Two days later he murdered two foster sisters, aged five and 14, and stabbed another woman on 24 August.