由研究者对研究人群实施了人为干预的研究为（）
A．描述流行病学研究
B．病例对照研究
C．队列研究
D．实验流行病学研究
E．分析性研究
参考答案：D
根据句意及首字母提示完成单词拼写。
1. All of us are s______ to hear that bad news.
2. I lost my knife. I looked for it e______ but I can't find it.
3. The window is b______. We need to repair it.
4. It's too dark in your study. Please turn on the table l______.
5. Today many things are made of p______, for example, bottles, plates, bowls and so on.
《我的信仰》是（）的一篇演讲词。
A.霍金
B.史怀泽
C.韦伯
D.爱因斯坦
