subject

Compared meaning: the main thing discussed or shown in a work (noun).

比较义项：谈话、写作或艺术作品中被讨论或表现的主题（名词）。

• topic

  Topic is the neutral, general word for a specific point being talked about, written about, or debated; it names the exact matter under discussion, not a broad field.

  topic 是中性、通用的词，指谈话、写作或辩论中正在讨论的具体一点，指明确的讨论内容，而不是一个宽泛的领域。

  Today's agenda has only one topic: the new budget proposal.

  今天的议程只有一个主题：新的预算提案。

• subject 本词

  Subject covers a broader range than topic, including formal or serious matters and, especially, school courses; it commonly appears in phrases like 'favorite subject' or 'change the subject.'

  subject 涵盖的范围比 topic 更广，既包括正式或严肃的议题，也常指学校的科目，常见搭配有“favorite subject（最喜欢的科目）”“change the subject（转移话题）”。

  Math was never my favorite subject in high school.

  数学在高中从来都不是我最喜欢的科目。

• theme

  Theme is more literary and abstract: the underlying idea, message, or central thread running through a piece of writing, film, or artwork, rather than a specific point discussed.

  theme 更偏文学化、更抽象：指贯穿一篇作品、一部电影或一件艺术作品的深层思想、信息或中心线索，而不是被讨论的具体一点。

  The film explores the theme of loss and redemption.

  这部电影探讨了失去与救赎这一主题。

Topic is neutral: the exact point being discussed. Subject is broader, covering serious matters and school subjects, as in 'favorite subject.' Theme is literary: the central idea running through a work of writing or art. Other senses of subject and theme are not compared here.

topic、subject、theme 在“主题”这一意义上很接近，但语域和范围不同：topic 中性、具体，指正在讨论的那一点；subject 范围更广，既可指正式议题，也常指学校的科目，并有“change the subject（转移话题）”这类固定搭配；theme 更偏文学、艺术化，指贯穿作品的中心思想或基调，而非某个具体的讨论点。这里不比较 subject 的“臣民”“语法主语”“受……支配的”等意义，也不比较 theme 的“主题曲”“主题乐园”等意义。

Compared meaning: a school course or academic field (noun).

比较义项：学校课程或学术领域中的“科目/学科”（名词）。

• subject 本词

  Names a specific class or topic taught in school, like History or Math; used in everyday talk about timetables, grades, and favorite classes.

  指学校或课程中的一门具体科目，比如历史或数学；常用于日常谈论课程表、成绩和喜欢的科目。

  Math was never my strongest subject in school.

  数学在学校里从来都不是我最擅长的科目。

• study

  Refers to a broader academic field or discipline, often phrased as the study of X or as the plural studies; more formal, common in university contexts like linguistics or environmental studies.

  指更广泛的学科领域，常以“是……的研究”这样的说法表达，或用复数studies构成学科名称；语气更正式，常见于大学语境，例如语言学或环境研究。

  Linguistics is a fascinating study of how languages change over time.

  语言学是一门研究语言如何随时间演变的有趣学科。

Both can mean a course or field of learning, but subject is everyday: one specific class in school, like History. Study is more formal, naming a broader academic field, often as 'the study of X' or the plural 'studies,' as in linguistics or environmental studies.

这两个词在“科目、学科”这一意思上很接近，但subject更日常，指学校课程表里的一门具体科目；study更正式，指一个学术研究领域，常以“the study of X”这样的说法或构成“studies”学科名来表达。这里不比较subject表示语法中的“主语”或“臣民”的意思，也不比较study作动词“学习”或作名词“研究报告”的意思。