To speak about the political system of the country, you need thу appropriate vocabulary.
  
Parliament -  in some countries, a group of people who make the laws for the country;
 
Congress - the group of people who make laws in the United States. Congress consists of the Senate and the House of Representatives;
 
Senate - a part of a government in some countries;
 
Term - the fixed period of time when someone does an important job or is in a particular place;
 
Declare - to announce something publicly or officially;
 
Sign - to write your name on something to show that you wrote/painted, etc it or to show that you agree to it;
 
Determine - to decide what will happen;
 
Commander-in-chief - a ​commander in ​charge of all the ​armed ​forces of a ​country or of all the ​forces ​fighting in a ​particular ​area or ​operation;
 
Vote - to show your choice or opinion in an election or meeting by writing a cross on an official piece of paper or putting your hand up;
 
Supreme Court - the court of law that has the most authority in a state or country;

Amendment - a change in the words of a document, or the process of doing this;
 
Armed forces - a country's military forces, for example the army and the navy.
 
Examples.
 
The government has been elected for another four-year term.
  
Who did you vote for?
  
It is important to have strong armed forces.