What are the four endpoints of China's two islands and three straits?

Two islands: Taiwan Province Island; Hainan Island;

Three Straits: Qiongzhou Seafood, Bohai Seafood and Taiwan Province Strait;

Four endpoints: the northernmost point-the center line of Heilongjiang main channel north of Mohe River in Heilongjiang Province; The southernmost tip-Zengmu shoal; The easternmost point-the intersection of the central lines of the main waterways of Heilongjiang and Wusuli rivers; The westernmost point-Pamirs Plateau.