在评价期间所发生干预计划之外的重要条件,如世界无烟日、食物供应变化属于()。
A.回归因素
B.选择偏倚
C.测试因素
D.成熟因素
E.历史性因素
参考答案:E
28. --- Is Bob still performing?
--- I’m afraid not. He is said _____ the stage already as he has become an official.
A.to have left
B.to leave
C.to have been left
D.to be left
“有明显的发汗作用”的是()
A.温水浴
B.热水浴
C.凉水浴
D.冷水浴
E.不感温水浴