专业技术人员依照法律或合同、协议享有特定权益和承担相应的义务
参考答案:对
电子在电场中运动时,仅受电场力作用,其由a点运动到b点的轨迹如图中虚线所示。图中一组平行等距实线可能是电场线,也可能是等势线,则下列说法中正确的是( )
A.不论图中实线是电场线还是等势线,a点的电势都比b点低
B.不论图中实线是电场线还是等势线,a点的场强都比b点小
C.如果图中实线是电场线,则电子在a点动能较小
D.如果图中实线是等势线,则电子在b点动能较大
句型转换
1. You can't make a noise in the classroom(改为祈使句)
a noise in the classroom.
2. Run in the classroom(改为否定祈使句)
in the classroom.
3. Don't fight in school.(改为同义句)
in school.
4. He has to wear a school uniform at school.(改为一般问句)
He to wear a school uniform at school?
5. We can eat in the classroom.(改为否定句)
We eat in the classroom.