Mr. Jin, the headteacher of Yu Cai Middle school is ______ warm-hearted person.
A:a
B:an
C:the
D:/
质量为1500kg的汽车在平直的公路上运动,v﹣t图象如图所示.以下说法错误的是( )
- You are in a hurry. Where are you going?
- To the cinema. Jim _________ for me there!
某同学在显微镜下观察洋葱表皮细胞,经正确操作看清细胞后,他兴奋地把显微镜搬动给同桌同学看,结果视野变得很暗.要重新看清物像,先进行的操作应是( )