The Sumerians were the first people to migrate to Mesopotamia, they created a great civilization. Beginning around 5,500 years ago, the Sumerians built cities along the rivers in Lower Mesopotamia, specialized, cooperated, and made many advances in technology. The wheel, plow, and writing (a system which we call cuneiform) are examples of their achievements.
1 In a presidential system, the legislature and the executive do not have to be aligned and often work against each other. 2  Policy implementation can be much slower and more moderated, at least in the US system.
A presidential parliamentary democracy is a democracy in which the chief executive (usually termed the Prime minister or the Premier is selected from among the members of the â¦ Parliament (the legislature). presidential legislative democracy is a system of government that  has a legislative branch that makes laws. The presidential or  executive branch carries out the policies â¦ and laws. Answered. In Political Theory.