A.the problems made by rolling backpacks |
B.the advantage of backpacks |
C.the best backpacks for students |
D.how to lighten students’ backpacks |
A.his back and neck will be hurt |
B.his head and arms will be hurt |
C.his hands will be hurt |
D.his feet will be hurt |
A.7 kilos | B.8 kilos |
C.6 kilos | D.10 kilos |
A.will know how to use backpacks |
B.may feel their backpacks are lighter |
C.can learn how to enjoy them |
D.may do less homework |