Sun regained control of Kwangtung in early 1923, again with the help of mercenaries from Yunnan and from the Comintern. Undertaking a reform of the KMT, he established a revolutionary government aimed at unifying China under the KMT. That same year, Sun sent Chiang to spend three months in Moscow studying the Soviet political and military system. During _his_ trip in Russia, Chiang met Leon Trotsky and other Soviet leaders, but quickly came to the conclusion that the Russian model of government was not suitable for China. <sep>, Pronoun: his <sep>, A: Chiang <sep>, B: Leon Trotsky