how does the author illustrate that communism has been largely unsuccessful in the countries that have adopted it

The author illustrated that communism has been largely unsuccessful in the countries that adopted it by citing the examples of Joseph Stalin of the Soviet Union and Mao Zedong of China whose reigns as communist leaders resulted in mass killings, oppression of opposers, and dictatorship instead of the equity and equality that a communist society should be known for.  

Explanation:

The article, 'An Introduction to Communism', by Jessica McBirney explained that the most prominent founding father of the ideology of communism was Karl Marx. Marz envisioned a society in which the workers would form a revolution against the ruling class because they felt that they were being oppressed. Such revolutions did occur in Russia leading to the formation of the Soviet Union, as well as China.

However, the leaders of these societies did not really practice ideal communism for their rulerships were marked by the mass killing of political dissenters, and dictatorship by the rulers instead of the equality of social classes that Karl Marx proposed.

none because there is no words that describe a noun and give a mood

i don't know and i don't care .