◎ 题干
I want to know how long________________________
[     ]
A.has he been back
B.has he come back
C.he has been back
◎ 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“I want to know how long________________________[ ]A.has he been backB.has he come backC.he has been back…”主要考查了你对  【宾语从句】  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。