/fill: 用一种方块填满两个角之间的区域，可选择做成空心、只保留外壳，或只替换特定方块。
语法
<尖括号> 内为必填，[方括号] 内为可选。 /fill 有 4 种写法：
/fill <from: position> <to: position> <tileName: block> <blockStates: block_state_array> [oldBlockHandling: fillmode]
/fill <from: position> <to: position> <tileName: block> [oldBlockHandling: fillmode]
/fill <from: position> <to: position> <tileName: block> <blockStates: block_state_array> <oldBlockHandling: replace> [replaceTileName: block] [replaceBlockStates: block_state_array]
/fill <from: position> <to: position> <tileName: block> <oldBlockHandling: replace> [replaceTileName: block] [replaceBlockStates: block_state_array]