Below is the detailed explanation of citizenship and the four bases to obtain citizenship:

Citizenship
Citizenship refers to the status of being a member of a particular country and having the rights, privileges, and responsibilities that come with it. It is a legal bond between an individual and a nation, granting them protection under the country's laws and giving them the right to participate in its political process.

The four bases to get citizenship are:

1. Birth
Citizenship by birth is acquired automatically when a person is born within the territorial limits of a country. This principle is often referred to as jus soli, meaning "right of the soil." For example, a person born in the United States is automatically granted US citizenship.

2. Descent
Citizenship by descent is acquired through one's parents' citizenship. This principle is also known as jus sanguinis, meaning "right of blood." For instance, if both parents are citizens of a particular country, their child may be eligible for citizenship in that country, even if they are born abroad.

3. Naturalization
Naturalization is the process by which an individual becomes a citizen of a country they were not born in. This process typically involves fulfilling certain residency requirements, passing a citizenship test, and taking an oath of allegiance to the country. Naturalized citizens enjoy most of the same rights as citizens by birth.

4. Marriage
In some countries, citizenship can be acquired through marriage to a citizen of that country. However, the process and requirements for obtaining citizenship through marriage vary widely from one country to another. Some countries may require a certain period of marriage before citizenship is granted, while others may have additional conditions.
By understanding these four bases of citizenship, individuals can determine their eligibility for citizenship in a particular country and take the necessary steps to acquire it.