---How long have you been studying in No.2 Middle School?

---Less than half a year.

---So it will be two years and a half _______ you graduate from this school.[ ]

A.when  

B.after        

C.before    

D.while

颅中窝骨折易损伤的神经是（）

A.视神经

B.嗅神经

C.第Ⅸ～Ⅻ脑神经

D.听神经

E.面神经