This question is not complete, here is the passage attached to the question:
Read this paragraph from chapter 5 of The Prince.
Whenever those states which have been acquired as stated have been accustomed to live under their own laws and in freedom, there are three courses for those who wish to hold them: the first is to ruin them, the next is to reside there in person, the third is to permit them to live under their own laws, drawing a tribute, and establishing within it an oligarchy which will keep it friendly to you. Because such a government, being created by the prince, knows that it cannot stand without his friendship and interest, and does its utmost to support him; and therefore he who would keep a city accustomed to freedom will hold it more easily by the means of its own citizens than in any other way.
EXPLANATION
The most important idea the author want the readers to know is that THERE ARE THREE MEANS OF HOLDING A NEWLY ACQUIRED STATE THAT IS ACCUSTOMED TO FREEDOM.
From the passage, we can see that the central idea that the author was talking about are the methods that a prince can use to manage conquered people, who are accustom to freedom.
It was stated in the passage that the best way to rule such people is to ruin them, to reside in their town in person and to allow them to live under their own laws. By doing these three things, a prince can easily create a friendly government, which will be loyal to him.
