单选题 Freeman and slave, patrician and plebeian , lord and serf, guild-master and journeyman, in a word, oppressor and oppressing , stood in constant opposition to one another, carried on an uninterrupted , now hidden, now open fight, a fight that each time ended, either in a revolutionary re-constitution of society at large, or in the common rain of the contending classes.

【正确答案】 B

【答案解析】[解析] 此处应为oppressor and oppressed。根据句中的Freeman and slave，patrician and plebeian，lord and serf guild-master and journeyman可知，每组词都是相互对立的关系。由此可知B项要表达的是压迫者和被压迫者。现在分词oppressing应改为过去分词oppressed，意思是“被压迫者”，故B项有误。