some teenagers don’t realize is difficult life can be after they get addicted to drugsA

问题补充：

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

答案：

(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。