A:To look
B:Looking
C:Having looked
D:Look
想一想,说一说。
在春天还有什么醒了?
醒了的动物有:____。
醒了的植物有:____。
读一读,给下列句子排序,在括号里写阿拉伯数字即可。
____It's green.
____I like Nancy's home.
____Why?
____What colour is it?
____Do you like Nancy's home or Danny's home?
____Because' the dining room is so big. I like the colour too.
如图所示,两根平行放置的长直导线a和b载有大小相同、方向相反的电流,a受到的磁场力大小为F1,当加入一与导线所在平面垂直的匀强磁场后,a受到的磁场力大小变为F2,则此时b受到的磁场力大小变为( )