英语翻译Which of the following can NOT be used as the subject(主语

英语翻译
Which of the following can NOT be used as the subject(主语）?
A.Mary B.Walking along the street C.THEY D.feed the animals
对她来说读完这本书是不可能的
____________________reading the book
能把你的字典借给我吗?
Can you________________your dictionary?
这个问题使我很不高兴
This problem_________________