One of the most important civics topics on the citizenship test is the structure of the U.S. government. It is split into three branches so that no single part becomes too powerful — a system called separation of powers.
1. The Legislative Branch (Congress)
Congress makes the laws. It has two parts:
- The House of Representatives — 435 voting members, based on each state’s population.
- The Senate — 100 members, two from each state.
2. The Executive Branch (the President)
The executive branch enforces the laws. It is led by the President, who is also the Commander in Chief of the military, supported by the Vice President and the Cabinet.
3. The Judicial Branch (the Courts)
The judicial branch reviews and interprets the laws. The highest court is the Supreme Court of the United States, which has nine justices.
Checks and balances
Each branch can limit the others. For example, Congress writes laws, the President can veto them, and the courts can rule whether a law is constitutional. This balance is a favorite topic on the civics test.
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The legislative branch: Congress
Congress writes the laws. It has two parts, the Senate and the House of Representatives, and the test asks about both. There are 100 senators, two from each state, serving six-year terms; each state has two senators so that small states have equal representation with large ones (the Great Compromise). There are 435 voting members of the House, serving two-year terms; states with larger populations have more representatives. Representatives serve shorter terms so that they more closely follow public opinion. Senators represent all the people of their state and are elected by them. Congress also has the power to declare war, and the Speaker of the House leads the House.
The executive branch: the President
The President is in charge of the executive branch, which carries out and enforces the laws. The President serves a four-year term and can serve only two terms, a limit set by the 22nd Amendment to prevent any one person from holding too much power. The President signs bills into law, can veto bills, appoints federal judges and Supreme Court justices, is Commander in Chief of the military, and sets foreign policy. If the President can no longer serve, the Vice President becomes President; if both cannot serve, the Speaker of the House is next. The executive branch also includes the Cabinet, whose members advise the President and run federal departments such as State, Defense, Treasury, Justice, Homeland Security, and Labor. Test questions ask you to name two Cabinet-level positions; “Secretary of State” and “Attorney General” are common answers.
The judicial branch: the courts
The judicial branch reviews laws, explains laws, resolves disputes, and decides whether a law goes against the Constitution. The highest court is the Supreme Court, which has nine justices; five are usually needed to decide a case. Justices serve for life so that they are independent of politics and free from outside influence. The Chief Justice of the United States is currently John Roberts. Federal courts below the Supreme Court include the courts of appeals and district courts.
Why three branches: checks and balances
The Constitution divides power so that no single part of government becomes too powerful. Each branch can limit the others. Congress passes a law; the President can veto it; Congress can override the veto with a two-thirds vote; the courts can strike the law down if it violates the Constitution; and the President appoints judges only with Senate confirmation. The test asks “There are three branches of government. Why?” and accepts “so one part does not become too powerful,” “checks and balances,” or “separation of powers.”
Federal versus state powers
Some powers belong only to the federal government: printing money, declaring war, creating an army, making treaties, and setting foreign policy. Others belong only to the states: providing schooling and education, providing protection (police), providing safety (fire departments), issuing driver’s licenses, and approving zoning and land use. The 10th Amendment says that powers not given to the federal government belong to the states or to the people. Your own state has a Governor as the head of its executive branch and a capital city where the state government meets; both are test questions.
Quick review list
- Legislative: Congress (Senate 100, House 435); makes laws.
- Executive: President, Vice President, Cabinet; enforces laws.
- Judicial: Supreme Court (9 justices) and federal courts; reviews laws.
- Senate term 6 years; House term 2 years; President 4 years (two-term limit); justices for life.
- Names to check before your interview: President, Vice President, Speaker of the House, Chief Justice, your Governor, your Senators, your Representative.
Last reviewed and expanded by the USCitizenTestPractice Editorial Team in September 2026, based on the USCIS Policy Manual, the official 2025 civics test materials, and current USCIS fee and form instructions. This is an independent study resource, not legal advice.
