leaf

Compared meaning: the leaves of a plant (noun).

比较义项：植物的叶子（名词）。

• leaf 本词

  Refers to one single leaf; a countable noun, so it takes 'a' and has the plural 'leaves'; used when talking about an individual leaf falling, changing color, or being examined closely.

  指单独的一片叶子，是可数名词，可用“a”并有复数形式“leaves”；用于描述单片叶子的掉落、变色或被仔细观察的情形。

  A yellow leaf fell slowly from the tall tree.

  一片黄叶从高高的树上缓缓飘落。

• foliage

  An uncountable noun for the leaves of a plant or tree collectively; used to describe the overall mass or density of leaves, as in 'thick foliage' or 'autumn foliage', never with 'a' or a plural form.

  指植物或树木上叶子的整体，是不可数名词；用于描述叶子整体的茂密程度或数量，如“thick foliage”（茂密的树叶）或“autumn foliage”（秋叶），不能加“a”或变为复数形式。

  The dense foliage made it hard to see through the forest.

  茂密的树叶让人很难看穿森林。

Leaf and foliage both mean the leaves of a plant. Leaf is countable, meaning one single leaf. Foliage is uncountable, meaning all the leaves of a plant together, describing their overall thickness. Leaf's other meaning, like a page in a book, is not compared here.

leaf 和 foliage 在“叶子”这个意思上很接近，但语法和侧重点不同：leaf 指单独一片叶子，是可数名词；foliage 指一株植物或一棵树上所有叶子的整体，是不可数名词，强调茂密感。这里不比较 leaf 的其他义项，如书页或桌子的活动搁板。