I'll never forget the days ________ I learn hard in my senior high school, ________ changed my whole life．

1. A.
   that; which
2. B.
   when, which
3. C.
   which, when
4. D.
   that; that

I’ll never forget the days 　　 I learn hard in my senior high school, 　　 changed my whole life.

A. that; which　 B. when, which　　 C. which, when　　　 D. that; that

I’ll never forget the days 　　 I learn hard in my senior high school, 　　 changed my whole life.

A．that; which　 　　　　　　 B．when, which C．which, when　 　 D．that; that