来自桂良军的问题
【分析一下这个英语长句的各个成分（好难懂）DuringthesecondhalfofthenineteenthcenturyintheUnitedStatesboththeimpetustoproducelandscapeartandthesubjectoflandscapealteredappreciablyasthepressureofeventssur】
分析一下这个英语长句的各个成分（好难懂）
DuringthesecondhalfofthenineteenthcenturyintheUnitedStatesboththeimpetustoproducelandscapeartandthesubjectoflandscapealteredappreciablyasthepressureofeventssurroundingtheCivilWarwitnessedtheemergenceofanewnationalconsciousness.
