如图所示的虚线区域内，充满垂直于纸面向里的匀强磁场和竖直向下的匀强电场。一带电粒子a（不计重力）以一定的初速度由左边界的O点射入磁场、电场区域，恰好沿直线由区域右边界的O′点（图中未标出）穿出。若撤去该区域内的磁场而保留电场不变，另一个同样的粒子b（不计重力）仍以相同初速度由O点射入，从区域右边界穿出，则粒子b                
（   ）

修改病句。

同学们参加了这项光荣而艰巨的任务。

Where are they?

    This is Tommy's bedroom(卧室). You can see a small bed 1the room. There's a toy(玩具)on the bed. You can see a light（灯）on the drawer. 2the photo? It's on the drawer，too. You can see 3on the chair. Where are the plants? They are4. The alarm clock, the pen and a cup 5on the table. 6you see a math book? Yes, it's on the floor. 

Mary looks ____(傻的) in the picture.

大棚种植的白菜喜获丰收，白菜长大的主要原料是（    ）