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：考查名词性从句。第一空是主语从句，从句中缺少宾语所以用关系what，第二空是表语从句，此句是一个感叹句，空后面的词是形容词difficult所以用how修饰，故选A。