题型:判断题 In speaking, the choice of words is of the utmost importance. But too often careless use of words______a meeting of the minds of the speaker and listener.A.stirsB.preventsC.destroysD.offers 查看答案
题型:判断题 下列组合中,依次属于种群、群落和生态系统的一组是()①生活在人大肠内的微生物②某一池塘中的全部鱼类③肺炎患者肺部的肺炎双球菌④一根枯木及其上所有生物A.①②④C.②③④C.③②①D.③①④ 查看答案