翻译一句话（不过有点难）

In political science, there are many types of division of the democratic system approach, from the institutional division of political parties, such as two-party system and multi-party system; from the voting system division, such as a single constituency system and proportional representation and so on

In politics, there are many types of democratic system division method, from the political party system, such as the two-party system and the system came, From voting system, such as single constituency in system and proportional representation, etc。

in political science, there are several methods to devide the types of democracy.devided by partyism, there are bipartisan system and multipartism, and by voting system, there are unitary electoral district system and proportional representation.