--______ we clean the classroom at once?

--No, you _____. You____ clean it after school.

A．Must, needn’t, may

B．Must, mustn’t, can

C．Shall, can’t, must

D．Need, mustn’t, may

用抗体修饰的靶向制剂称为

A．被动靶向制剂
B．主动靶向制剂
C．物理靶向制剂
D．化学靶向制剂
E．pH敏感靶向制剂