affirm

Compared meaning: to state firmly that something is true (verb).

比较义项：坚定地宣称某事为真（动词）。

• assert

  Assert means to state a claim firmly and confidently, often without offering proof, and can sound forceful, insistent or even confrontational, as when pushing an opinion or a right.

  assert 表示坚定而自信地提出主张，往往并不提供证据支持，语气可能显得强硬、坚持甚至带有对抗性，例如坚持己见或维护权利时常用此词。

  He asserted that the company's financial records were completely accurate.

  他坚称公司的财务记录是完全准确的。

• affirm 本词

  Affirm means to state firmly that something is true, typically confirming or validating an existing statement, decision or belief; it sounds more formal and supportive than confrontational.

  affirm 表示郑重地确认某事为真，通常用于证实已有的说法、决定或信念，语气比 assert 更正式、更具支持性，而非带有对抗意味。

  The board members affirmed that the merger would go ahead as planned.

  董事会成员们确认合并将按计划进行。

Assert and affirm both mean to state firmly that something is true, but assert sounds forceful, often pushing an opinion without proof. Affirm means to confirm an existing statement, and sounds more formal and supportive. This does not compare 'assert oneself', meaning to act confidently.

这两个词在此义项中都表示坚定地宣称某事为真，但语气和用法略有不同：assert 更强调主动、坚决甚至强硬地提出主张，而 affirm 更强调郑重地确认或证实已有的说法，语气更正式、更具支持性。这里不比较 assert 的“表现自信、维护自己的权利（assert oneself）”这一义项。

Compared meaning: to prove or state that something is true (verb).

比较义项：证实、确认某事是真实的（动词）。

• confirm

  General, everyday word for establishing that something is true or as expected; used for facts, plans, bookings, and suspicions alike, often with a that-clause.

  这是一个通用的日常词，表示证实或确定某事是真实的或与预期相符，可用于事实、计划、预订和猜测等，常接that从句。

  Please confirm your appointment by replying to this email.

  请回复此邮件以确认您的预约。

• affirm 本词

  Formal; to state something positively and confidently as true, typically one's own belief, identity, or statement, rather than backing up someone else's account with evidence.

  较为正式；表示明确、自信地陈述某事为真，通常是陈述自己的信念、身份或说法，而不是用证据支持他人的说法。

  The witness stood up to affirm that her statement was true.

  证人站起来确认她的陈述是真实的。

• corroborate

  Formal or legal; to add independent evidence or testimony that supports someone else's existing claim or story, usually taking a noun object like 'story' or 'alibi', not a that-clause.

  较为正式（常用于法律语境）；表示提供独立的证据或证词来支持他人已有的说法或陈述，通常接名词宾语（如story、alibi），而不是that从句。

  Witnesses were able to corroborate her story about the accident.

  目击者能够证实她对事故的描述。

Confirm, affirm, and corroborate all mean to show something is true, but usage differs. Confirm is the common, neutral word. Affirm is formal, meaning to state one's belief firmly. Corroborate is formal too, meaning to support someone else's claim with independent evidence, often in law.

这三个词都表示证实、确认某事为真，但语气和搭配不同：confirm最常用、最中性，日常和正式场合都可用；affirm更正式，强调坚定地陈述（通常是自己的）信念或说法；corroborate也很正式，强调用独立证据或证词支持他人已有的说法，常见于法律和调查语境。这里不比较affirm表示「宣誓效忠」或用于法律宣誓替代的义项。