Complex sentence: The two works had a powerful nationwide impact among readers, but in the next year, 1957, Liu was labeled a "rightist" and expelled from the Communist Party (see Hundred Flowers Camapaign).
Split into simpler sentences: The two works had a powerful nationwide impact among readers. In the year following the publication of "On the Bridge Worksite" and "The Inside Story of Our Newspaper," 1957, Liu was labeled a "rightist" and expelled from the Communist Party (see Hundred Flowers Camapaign).