◎ 题干
Though he tried many ways to solve the problem, ______ worked; he decided to turn to his tutor for
help.    
[     ]
A. none of which      
B. all of them    
C. none of them      
D. all of which
◎ 答案
查看答案
◎ 解析
查看解析
◎ 知识点
    根据n多题专家分析,试题“Though he tried many ways to solve the problem, ______ worked; he decided to turn to his tutor forhelp.[ ]A. none of whichB. all of themC. none of themD. a…”主要考查了你对  【人称代词】【不定代词】  等知识点的理解和应用能力。关于这些知识点的“档案”,你可以点击相应的链接进行查看和学习。