功似龙骨而长于软坚散结的药物是（）
A.石决明
B.牡蛎
C.磁石
D.珍珠母
E.羚羊角
参考答案：B
We all feel puzzled why the students _____ the same mistakes repeatedly in exams.
A．were making
B．have been making
C．had made
D．will be making
天气预报可分为哪些，以下不正确的是（）
A.天气形势预报
B.气象要素预报
C.大风降温预报
