Make up a math story in units of length. There are meters, decimeters, centimeters, millimeters and kilometers at the second level.

One morning, Scampy went to his mother's bed and said to her, "Mom, mom! I had a dream. " "What delicious food did you dream of?" Mom asked with a smile. The child thought for a moment, and then said, "In the morning, I got up from a 2m bed, picked up a 2m toothbrush, squeezed out 1 cm toothpaste to brush my teeth, and then washed my face and ate. I walked 200 meters to school, sat on a 5-meter-high desk and chair, took out a 2-meter-long pencil case and a 5-mm-thick exercise book, and began to do the problem. In physical education class, the teacher organized the top sportsmen in the class, including me, to run two and a half laps along the 400-meter school playground runway, which is exactly 1000 meters. Mom, do you think I'm tired? . . . . . ""Tired, tired, tired, my son is really tired. " Mother said anxiously, "Tomorrow weekend, your father and I will definitely drive you for a ride in the suburbs."