我们规定电流方向是 [ ]
A．正电荷定向移动的方向
B．负电荷定向移动的方向
C．正电荷移动的方向
D．负电荷移动的方向
答案：A
—Is this picture very nice ?
—_______[ ]
A. Yes, it isn't.
B. Yes, it is.
C. No, it is.
She is ___ at all the subjects, and she is ___ student in her class. [ ]
A. good; best
B. well; best
C. good; the best
D. well; the best
