问题补充：
单选题Ijustdon’tunderstand______thatleadstosomanyteenagersbecomingaddictedtoplayingcomputergames.A.why it doesB.what it doesC.what it isD.why it is
答案：
C解析考察强调句，强调句的特点是去掉it was that之后句子完整，该句强调的是what，去掉强调句后的句子是 I just don’t understand what leads to so many teenagers becoming addicted to playing computer games.
