Complex sentence: Cai served as Deputy Chief of the General Staff of the PLA from 2011 to 2012, and was appointed Commander of the Nanjing Military Region in 2012, and attained the rank of general ("shang jiang") in 2012.
Split into simpler sentences: Cai served as Deputy Chief of the General Staff of the PLA from 2011 until 2012, when was appointed Commander of the Nanjing Military Region. He attained the rank of general ("shang jiang") in 2012.