Modern Democracies can not exist without political parties because of the functions that the political party's play:- 
1)They contest in Elections.
2)They put forward different policies and programmes. 
3)They play a decisive role in the making of Laws.
4)They form and run the government.
5)Play the role of Opposition in to the Ruling Party
6)They shape public opinion, as they raise and highlight issues.
7)They provide people access to government machinery and welfare schemes implemented by the government.

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Yours, Jahnavi