grumble

Compared meaning: quiet, unclear speech or a low speaking sound (verb/noun).

比较义项：小声、含糊地说话或发出的低语声（v./n.）。

• mutter

  A verb meaning to speak in a low, indistinct voice, often to oneself out of annoyance or private thought; the focus is on being hard to hear or understand, not on complaining.

  动词，指压低声音、含糊地说话，常常是自言自语，出于烦恼或心事；重点在说话含糊难懂，不一定是抱怨。

  He muttered something under his breath as he left the room.

  他离开房间时低声嘟囔了一句。

• grumble 本词

  A verb meaning to complain in a bad-tempered, dissatisfied way; the emphasis is on the negative, complaining attitude rather than the volume or clarity of the voice.

  动词，指以不满、坏脾气的语气抱怨、发牢骚；重点在负面、抱怨的态度，而不是说话的音量或清晰度。

  She grumbled about having to work overtime again.

  她又抱怨要加班了。

• murmur

  A noun for a soft, continuous, indistinct sound of voices, often from a group; it is neutral in tone and describes a sound, not an act of complaining or muttering alone.

  名词，指低沉、连续、听不清内容的说话声，常来自一群人；语气中性，描写的是声音本身，而不是抱怨或独自嘟囔的动作。

  A murmur of agreement passed through the crowd.

  人群中传来一阵低声的附和。

These words describe quiet, unclear speech or sound. Mutter (verb): speak low and unclear, often alone, from annoyance. Grumble (verb): complain in a bad-tempered way; the focus is the attitude, not the volume. Murmur (noun): a soft, continuous, unclear sound of voices, from a group.

这三个词都描写轻声、不清楚的说话方式或声音，但语气和词性不同：mutter 强调说话含糊难懂，常因心事或不满而自言自语；grumble 强调带着不满、抱怨的语气发牢骚，不一定压低声音；murmur 在这里是名词，指低沉连续、听不清内容的说话声，语气中性，常用于描写人群或背景的嘈杂声。这里不比较 grumble 表示“肚子咕咕叫”的用法，也不比较 murmur 作动词（低声说）或医学上“心脏杂音”的用法。

Compared meaning: a spoken complaint about something (noun).

比较义项：抱怨、牢骚（名词）。

• murmur

  Refers to a soft, subdued complaint, often voiced quietly by a group rather than stated loudly or directly; frequently appears in phrases like 'a murmur of protest'.

  指轻声、低沉的抱怨，常常是一群人小声表达不满，而不是大声或直接地抱怨；常用于诸如“a murmur of protest”这样的短语中。

  A murmur of protest rippled through the audience when the show was cancelled.

  演出取消时，观众席间泛起了一片抗议的低语声。

• grumble 本词

  A specific, personal complaint about a minor annoyance, used as a countable noun or verb, typically one person's low-toned, often repeated grievance rather than a group's quiet murmuring.

  指针对某件小烦恼的具体、较个人化的抱怨，可用作可数名词或动词，通常表示一个人低沉不满、甚至反复发出的抱怨，而不是一群人发出的轻声低语。

  His only grumble about the new job was the long commute every day.

  他对新工作唯一的抱怨就是每天上下班的路程太长。

Both nouns mean a complaint, but differently. Murmur is a soft, quiet complaint, often voiced by a group rather than stated loudly or directly. Grumble is a personal complaint about a small annoyance, often said by one person in a low-toned, sometimes repeated way.

两者都指因不满而发出的抱怨，但murmur强调声音轻柔低沉、常常是一群人小声表达的不满；grumble强调个人化、针对具体小事的、语气不满的抱怨，可反复发生。这里不比较murmur表示“潺潺水声”“低沉杂音”等其他义项，也不比较grumble表示“隆隆声”（如雷声）的其他义项。