form

Compared meaning: the outline or structure of something (noun).

比较义项：形状（名词）。

• shape

  Shape refers to the outer outline or silhouette of an object; it's the common, everyday word for describing what something looks like from the outside.

  shape指物体的外部轮廓或剪影，是日常英语中描述某物外观最常用的词。

  The kite was cut into the shape of a bird.

  这只风筝被剪成了鸟的形状。

• form 本词

  Form is a more formal or literary word for the overall structure or configuration of something, often used in artistic, scientific or abstract contexts, not just outline.

  form是较为正式或文学化的词，指某物的整体结构或形态，常用于艺术、科学或抽象语境，而不仅仅是外部轮廓。

  The sculpture captured the human form in bronze.

  这座雕塑用青铜塑造出了人体的形态。

Shape and form can both mean the outline of something. Shape is the common word for an object's outer outline. Form is more formal or literary, meaning the overall structure, often used in art or science. Not compared: form meaning a document.

这两个词在「形状」这一义项上意思相近，但语气不同：shape更口语化，强调物体的外部轮廓；form更正式、书面化，强调整体结构或形态，常见于艺术、科学等语境。这里不比较form表示「表格」的义项。

Compared meaning: to give something a particular shape (verb).

比较义项：塑造，使某物具有特定形状（动词）。

• form 本词

  Form describes parts, people, or ideas coming together into a shape or structure; it rarely means physically working a material by hand, and often appears with abstract nouns like opinion, plan, or habit.

  form 通常指若干部分、人或想法聚合在一起形成某种形状或结构，很少指用手直接加工某种材料，常与“意见、计划、习惯”等抽象名词搭配使用。

  The students formed a straight line outside the classroom door.

  学生们在教室门外排成了一条直线。

• shape

  Shape is the general, everyday word for giving any material or idea a particular form, including hard materials like wood or stone that cannot be poured or pressed into a mold.

  shape 是最通用、日常的词，可用来表示把任何材料或想法塑造成某种形态，即便是木头、石头这类不能倒入模具或按压成形的坚硬材料，也能用 shape。

  He used a small knife to shape the piece of wood.

  他用一把小刀把这块木头削出了形状。

• forge

  Forge is a technical, narrower word: it specifically means to shape metal by heating it and hammering it, so it cannot replace the others for soft or non-metal materials.

  forge 是较专业、范围更窄的词，专指通过加热金属再锤打使其成形，不能用来加工柔软材料或非金属材料。

  The blacksmith forged a horseshoe from a glowing iron bar.

  铁匠把烧红的铁条打制成了一个马蹄铁。

• mold

  Mold implies pressing or pouring a soft, flexible material into or against a fixed pattern, or shaping someone's character over time through repeated influence.

  mold 表示把柔软、可塑的材料压入或倒入固定的模具中塑形，也可以指通过长期反复的影响来塑造一个人的性格。

  She pressed and molded the warm wax into a small heart.

  她把温热的蜡按压塑成了一个小心形。

All four mean to shape something. Form means parts or ideas joining into a structure. Shape is the general word for any material. Forge means to shape metal by hammering it hot. Mold means to press soft material into a pattern, or shape someone's character.

这几个词都表示“使某物具有特定的形状或形态”，但所用材料、方式和语气有所不同，容易被中国学习者混淆。这里不比较 form 作名词表示“表格”的用法，也不比较 forge 表示“伪造”的义项。