Final answer:
Presidential and parliamentary systems are both democratic republics, but differ in the relationship between the executive and legislative branches. Semi-presidential regimes combine features of both systems. Elections are central to maintaining democracy and facilitating popular participation, despite having some weaknesses.
Step-by-step explanation:
The two basic forms of democratic republic mentioned are presidential and parliamentary systems. In a presidential system, the president is both the head of state and the government, and is elected independently of the legislature, leading to a clear separation of powers. In a parliamentary system, the head of state and the head of government are distinct (often a monarch and a prime minister, respectively), and the executive branch derives its legitimacy from the legislative branch, often leading to a greater integration between the two branches. They are similar in that both forms elect officials to represent the interests of citizens, but they differ in the relationship between the executive and the legislature.
Semi-presidential regimes are different as they combine features of both presidential and parliamentary systems. A country with a semi-presidential regime has a president (elected by the people) and a prime minister (who usually needs the support of the legislature). This arrangement can contribute to a system of checks and balances similar to a presidential system, but it can also reflect the integration of powers seen in parliamentary systems.
Throughout different democratic regimes, there is an apparent connection between democracy and freedom, as democracies typically allow for greater political freedom and protection of civil liberties.
Elections are crucial to democracy and popular participation as they provide a mechanism for the public to express their will and hold their government accountable. However, weaknesses of popular elections can include low voter turnout, the influence of money in campaigns, and unequal access to the electoral process. Generally, to vote in the United States, a person must be a citizen, 18 years or older, and meet certain residency requirements. Additionally, civic participation can take many forms, and each method, including voting, has its own advantages and disadvantages.