教育实验共同具备的基本特征是（）。
A.有变革
B.可重复操作
C.有理论假说
D.有控制
E.全面科学
参考答案：A, B, C, D
At the age of 29, Dave was a worker, _____ in a small apartment near Boston and _____ what to do about
his future. [ ]
A. living; wondering
B. lived; wondering
C. lived; wondered
D. living; wondered
