2013高考英语总复习过关检测题：新人教版必修2Units 1～2（答案）
21．(2012·太原调研)In our class, the student leaders are on________duty every________few days.
A.the; a B．/; a
C./; / D.the; /
22．(2012·三明普高联考)We know playing computer games for a long time can harm one's________health.
A. regular B. magical
C. physical D. reliable
