YJ17卷烟机砂轮高度调节时,砂轮与切刀接触应有稍微变形为止。
参考答案:错
在下列各组物理量中,全部属于矢量的是( )
A.位移、时间、速度
B.速度、速度变化量、加速度
C.速度、速率、加速度
D.路程、时间、速度
—Why is the famous althlete absent from the game?
—He has been________to take part in competitions for a year because of taking drags.
A.arrested
B.forbidden
C.declined
D.scolded