1.水军 Internet Water Army
It means a group of Internet ghostwriters paid to post online comments with particular content
2.枪手 paid posters
It means netizens hired to leave fake comments and delete genuine ones
3.公知 public intellectual
It means a very educated person whose interests are studying and other activities that involve careful thinking and mental effort
4.意见领袖 opinion leader
It means a well-known individual or organization that has the ability to influence public opinion on a subject matter.