some teenagers don’t realize is difficult life can be after they get addicted to drugs.
A. What; how
B. That; how
C. What; what a
D. That; what
网友回答
(答案→)A. What; how
B. That; how
C. What; what a
D. That; what
解析：第一空是主语从句，what作realize的宾语，第二空是表语从句，how修饰difficult。句意：一些青少年所意识不到的是他们染上毒瘾之后生活是多么的艰难啊。