工业上采用 ____法制取氧气，这种方法属于 ____变化．
如图，已知正方形ABCD的边长为2，以C点为圆心将线段BC顺时针旋转60°，连接BP．PD，则PD的长是（ ）
I'm Tom. I have a friend. Her name is Lucy. She is ____.Her favourite food is ____. She is thirsty. She would like some ____ .Her water bottle is ____the table. Look! There is her photo ____the table.
已知七巧板的结构如图所示，请运用七巧板拼出1﹣9这九个数中的任意3个数字．说明：七巧板中的七块板可以不用完，但拼好后将图对应的编号写在拼出的图形中．
