- 問題詳情:AlittleboywasplayinginhissandboxonaSaturdaymorningehewasbuildingroadsandhousesinthesoftsand,hediscoveredalargestoneinthemiddleofthesandbox.Thelittleboypushedandpulled,buteverytimehethoughthehadmadesomeprogress,thestonetipped(傾斜)andthenfellb...
- 28709