Complex sentence: Sun's successor, Chiang Kai-shek, led the Northern Expedition in 1926-28, wiped out the Beiyang warlords in Beijing and other warlords in Southern and Northern China, after the unification, international recognition was given to the Nanjing based KMT regime.
Split into simpler sentences: Sun's successor, Chiang Kai-shek, led the Northern Expedition in 1926-28, which wiped out the Beiyang warlords in Beijing and other warlords in Southern and Northern China. After the unification, international recognition was given to the Nanjing based KMT regime.