How I wish __ more when I was at university, which is too late now. A. I would learn. B. I would have learned C. I had learned D. I learned
如图所示，直导线垂直于磁场方向放在水平向右的匀强磁场中，通以垂直纸面向里的电流，则直导线受到安培力的方向（ ） A．向上 B．向下 C．向左
如图所示，在半径为R的半圆形碗的光滑表面上，一质量为m的小球在水平面内作匀速圆周运动，周期为T,则该平面离碗底的距离h =______ .
日本福岛第一核电站发生严重的核辐射泄漏，日本政府向核电站附近居民发放碘片（127I），以降低放射性碘对人体的伤害．已知放射性碘（131I）的核电
百年前，梁启超先生曾在《少年中国说》中指出：少年智则国智，少年富则国富，少年强则国强，少年进步则国进步，少年雄于地球，则国雄于地球。
--Who’s your Chinese teacher?--Miss Zhang. She has taught ______ Chinese for two years.A．ourB．usC．oursD．we
My friend is a rather old-fashioned lady. She is always quite delicate and elegant（文雅的）, especially in her language. She and her husband were planning to attend a family party, so sh
若圆C的半径为1，圆心在第一象限，且与直线轴都相切，则该圆的标准方程是 （ ） A． B
与
的等差中项是 。