皮影戏又称（）
A.潮词
B.掌中戏
C.宋江戏
D.师公调
参考答案：A, D
The driver wanted to park his car near the roadside but was asked by the police ______.
A．not to do
B．not do
C．not to
D．do not
不能用来控制病例对照研究偏倚的是
A．采用多种对照B．应用盲法C．随机化分组D．限制某些人群进入研究对象E．分层分析
