A state of anarchy（无政府状态） exists when a country has no effective(实际的） government.

In an anarchy there is nobody to make decisions or enforce the laws.

An autocracy is the simplest form of government.

In an autocracy(独裁政府） the government is controlled by a single individual, known as the autocrat（独裁者）.

Whether or not an autocracy is successful, depends on the character and ability of the leader.

In an oligarchy (寡头政治）a small group of people controls the government.

Membership in this group often depends on family connections， wealth or military power.

In a republic(共和国）, individuals are elected to represent the citizens.

The power of the government in a republic is limited by a constitution(宪法）.

A constitution is a written document that makes the rules for a government to follow.

This limits the power of the government.

A constitution defines the relationship between the government and its citizens.