800里有____个百，也可以看成____个十，还可以看成____个一。

    This morning Jenny, Linda, Mary, Alice and Sally found five bags. Jenny found a brown bag in Classroom 208. In the bag is ____. Linda found a purple bag in Classroom 306.In the bag is ____. Mary found a green bag in Classroom 409.In the bag is ____.Alice found a red bag ____.In the bag is a yellow pencil. Sally found a blue bag ____.In the age is a watch.

把下列各数填在相应的大括号内：5，﹣2，1.4，﹣ $\frac{2}{3}$ ，0，﹣3.14159．

正数：{                             ，…}；

非负整数：{                             ，…}；

整数：{                             ，…}；

负分数：{                             ，…}．