Complex sentence: He took an active part in the subsequent battles against the Cossacks in the Khmelnytsky Uprising, fighting at the Battle of Berestechko and Battle of Bila Tserkva in 1651.
Split into simpler sentences: He took an active part in the battles against the Cossacks in the Khmelnytsky Uprising. He was part of the fighting at the Battle of Berestechko and Battle of Bila Tserkva in 1651.