Geography of Taiwan and Green Island to the southeast, separated from the northernmost islands of the Philippines by the Bashi Channel. The islands of Kinmen and Matsu near the coast of Fujian across the Taiwan Strait have a total area of ; the Pratas and Taiping islets in the South China Sea are also administered by the ROC, but are not part of the Taiwanese archipelago. The island of Taiwan was formed approximately 4 to 5 million years ago at a complex convergent boundary between the Philippine Sea Plate and the Eurasian Plate. In a boundary running the length of the island and
Government of the Republic of China separated from the mainland by the -wide Taiwan Strait. During that period, more than two million civilians, military personnel and government officials left the mainland for Taiwan. Chiang then declared Taipei as the provisional capital of the Republic of China on 7 December 1949, and left Chengdu for Taipei by air three days later when the city fell to the communists. Based on the Constitution of the Republic of China, the head of state is the President, who is elected by popular vote for a four-year term on the same ticket as the Vice-President. The President has authority over the