Under the constitution, the main duty of the National Assembly was to elect the President and Vice President for terms of six years. It also had the right to recall or impeach the President and Vice President if they failed to fulfill their political responsibilities. According to "National Assembly Duties Act," the National Assembly could amend the constitution with a two-thirds majority, with at least three-quarters membership present, as well as to ratify constitutional amendedments proposed by deputies of the Legislative Yuan. It could also change territorial boundaries. After the KMT moved to Taiwan, the Assembly's right to legislate was put into moratorium until at least half of all counties in the nation were again able to elect representatives via their County Assemblies. The responsibilities of the deputies of the Assembly, as well as of the Assembly as a whole, were derived from the directions of Dr. Sun Yat-sen.