会    变    大    变    小    的    书    包   

 你    想    发    明    什    么   ? 它    是    什    么    样    子    的   , 有    哪    些    功    能   ? 把    它    写    出    来    介    绍    给    大    家    吧   ! 可    以    参    考    下    面    的    提    示   , 想    想    自    己    要    写    的    内    容   。 还    可    以    把    你    想    发    明    的    东    西    画    出    来   , 帮    助    自    己    描    述   

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