Beijing showed off its close ties to Tehran on Wednesday by hosting Iran’s top diplomat days before an expected summit between President Trump and China’s leader, Xi Jinping. 周三，伊朗最高外交官访问北京，在特朗普总统与中国领导人习近平即将会面的前几天，北京展示了与德黑兰的密切关系。 China’s top diplomat, Wang…