下面不属于决定技术转移的成效的是()。
A.技术引进方
B.技术输出方
C.技术本身
D.技术创新
参考答案:D
—How old are you?
—I'm fifteen. I was born _______ 1990. [ ]
A. in
B. at
C. on
D. for
圆的半径缩短一半,圆的直径不一定缩短一半.______. (判断对错)