Following the ROC government's retreat to Taiwan on December 7, 1949, the Temporary Provisions together with martial law made the country an authoritarian one-party state despite the constitution. Democratization began in the 1980s. Martial law was lifted in 1987, and in 1991 the Temporary Provisions were repealed. The Additional Articles of the Constitution was passed to reflect the government's actual jurisdiction and realization of cross-Strait relations. The Additional Articles also significantly changed the structure of the government to a semi-presidential system with a unicameral parliament, which formed the basis of a multi-party democracy in Taiwan.