sister is twelve,and is a student.A. His ,sheB. Her,myC. They ,sheD. My ,these

sister is twelve,and is a student.
A. His ,she
B. Her,my
C. They ,she
D. My ,these

(答案→)A. His ,sheB. Her,myC. They ,sheD. My ,these解析：名词前通常用物主代词，所以C中they是人称代词，故不选，动词前作主语要用人称代词主格，而且第二个空后is，要用表示单数的单词，故B和D 不对，只能选A。

这下我知道了