For each top-level feature, or facet, there is a sub-tree of possible values.

对于每个顶级特性或方面，都有一个可能值组成的子树。

youdao

The key of a node is always greater than the keys of the nodes in its left sub-tree

节点的键始终大于它左边的子树中的节点的键

youdao

The key of a node is always smaller than the keys of the nodes in its right sub-tree.

节点的键始终小于它右边的子树中的节点的键。

youdao

During her time in Ghana, Warren stumbled upon women who collect the fallen nuts from the shea tree, indigenous to sub-Saharan Africa.

FORBES: Social Enterprise Spotlight: Just Markets For Ghana's Women

Ron Morano, a spokesman for Jersey Central Power and Light, where essentially all of its 1.1 million customers lost power, said the company was looking at ideas that include putting some sub stations underground and more aggressive tree-trimming.

WSJ: ConEd Storm Plan to Cost $1 Billion