Complex sentence: When he did return, he never regained the same power and influence he enjoyed in the years before he left, but he was able to keep his position in the National Assembly until it disbanded on September 30,1791.
Split into simpler sentences: When he did return, he never regained the same power and influence he enjoyed in the years before he left. However, he was able to keep his position in the National Assembly until it disbanded on September 30,1791.