How did both the allies and the central powers try to gain the support of americans?

To gain backing of Americans, both the Allies and Central Powers used Propaganda intended to influence opinion. Governments during the First World War keen massive capitals and huge quantities of effort to creating material intended to shape opinion and action worldwide. The labors of states to defend their actions, and to build global support, caused in some of the most influential propaganda ever shaped. 

in 1989, tiananmen square in beijing was the site of china’s main industries. china’s government headquarters. -pro-democracy demonstrations. (second choice)