题干
He didn’t work ________ the other students in his class, so he got the worst report card for the end-of-year exams.
A：as hardly a
B：so hardly a
C：so hard a
D：so hard so
答案(点此获取答案解析）
C
粒子，粒子仅在电场力的作用下，沿着电场线从M点运动到N点。粒子的速度随时间变化的规律如右图所示。以下判断正确的是：
