which university to attend，the girl asked her teacher for advice. (2013·四川，8)
A. Not knowing
B. Knowing not
C. Not known
D. Known not
网友回答
(答案→)A. Not knowing
B. Knowing not
C. Not known
D. Known not
解析：
句意为：因为不知道该上哪所大学，女孩求助于老师。句子主语the girl和动词know之间是主谓关系，所以应该用动词ing形式作状语，而动词ing形式的否定式是在其前加not，所以选A，从而排除B和表示动宾关系的C和D。