assume

Compared meaning: to think something is true without proof (verb).

比较义项：在没有确凿证据的情况下认定某事为真（动词）。

• assume 本词

  Neutral, everyday word for taking something as true casually or for the sake of argument, often with little or no real basis; the guess can later prove wrong.

  语气中性、随意，常用于随口认定某事为真或为了论证方便而假设，往往缺乏真实依据，事后可能被证明是错误的。

  Let's assume the bus is late again and leave five minutes early.

  我们就假设公交车又晚点了，提前五分钟出发吧。

• presume

  Suggests a supposition based on likelihood, prior knowledge or habit, often used formally or politely; implies more confidence that the guess is correct than assume does.

  暗示这一判断是基于可能性、已知情况或习惯做出的，语气较为正式或客气，比起 assume 更显得有把握，认为自己的判断是对的。

  I presume you already finished your homework before dinner.

  我猜想你晚饭前应该已经做完作业了吧。

Both words mean to think something is true without proof. Assume is neutral and casual; the guess may later prove wrong. Presume is formal, suggests a reasonable basis, and can sound polite. Not compared: presume meaning to infer from known facts, or act without permission.

这两个词都表示在缺乏确凿证据时认定某事为真，但语气和依据程度不同：assume 语气中性随意，常用于假设推理或毫无根据的猜测，事后可能被证明是错的；presume 语气更正式，暗示说话人有一定合理依据或习惯性推断，也常用于礼貌客套的场合。这里不比较 presume 表示“推测”（根据已知信息进行逻辑推断）或“擅自”（未经许可就认定或行事）的其他用法。

Compared meaning: to put on a false manner or feeling (verb).

比较义项：摆出或装出某种姿态、神情或情感，并非发自真心（动词）。

• assume 本词

  Suggests putting on an affected, often showy manner or air, mainly to look impressive; typically pairs with words like 'air', 'pose', or 'manner' rather than with specific emotions.

  表示摆出一种做作、炫耀的姿态或神情，主要是为了显得体面或重要；常与“air”“pose”“manner”等词搭配，而不是具体的情感。

  The butler assumed an air of great importance whenever the cameras were near.

  每当镜头靠近，那位管家就摆出一副煞有介事、神气十足的样子。

• feign

  Suggests deliberately pretending to have a specific feeling or condition in order to deceive others, not necessarily to look impressive; common with emotions like surprise, illness or interest.

  表示故意假装具有某种具体的感觉或状态，目的是欺骗他人，而不一定是为了显得体面；常与“惊讶”“生病”“兴趣”等情感搭配。

  He feigned enthusiasm about the extra work to avoid seeming lazy.

  他假装对额外的工作很有热情，免得显得懒惰。

Both words mean showing a feeling that is not sincere. Assume suggests putting on an affected, showy air, often with 'air' or 'pose'. Feign suggests pretending a specific feeling, like surprise or illness, to deceive someone. Not compared: assume meaning 'suppose' or 'take responsibility'.

assume 在此义项中强调摆出一种做作、炫耀的姿态或神情，常与“air”“pose”“manner”等词搭配，语气偏正式；feign 则强调故意假装具有某种具体的情感或状态以蒙骗他人，常用于“惊讶”“生病”“兴趣”等场合。两者都表示“并非发自内心的表现”，但装出的对象和目的不同。此处不比较 assume 的“假设”“承担（责任）”等其他常见义项。