Complex sentence: Dissatisfaction with the Articles prompted the Philadelphia Convention, which drafted the Constitution of the United States, under which Congress is a bicameral legislature divided into an upper house, the Senate, and a lower house, the House of Representatives.
Split into simpler sentences: Dissatisfaction with the Articles prompted the Philadelphia Convention, which drafted the Constitution of the United States. Under this document, Congress is a bicameral legislature divided into an upper house, the Senate, and a lower house, the House of Representatives.