keen

Compared meaning: sharp or strong in feeling, thought, or insight (adjective).

比较义项：感觉、思维或洞察力上的敏锐、尖锐（adj.）。

• acute

  Acute stresses the intensity of a sensation, feeling, or awareness, often in a formal or clinical tone, as in physical senses or careful analytical attention to detail.

  acute 强调某种感觉、情绪或意识的强烈程度，语气较为正式或偏医学化，常见于描述身体感官或对细节的缜密分析性关注。

  The detective had an acute awareness of small details that most people overlook.

  这位侦探对大多数人会忽略的细节有着敏锐的觉察力。

• keen 本词

  Keen is the everyday, informal word for someone perceptive or skilled, often paired with 'eye', 'mind' or 'sense', suggesting natural talent or enthusiasm rather than intensity.

  keen 是日常口语中形容某人敏锐或有天赋的常用词，常与“眼光”、“头脑”或“感觉”搭配，强调天生的才能或热情，而非强烈程度。

  She has always had a keen eye for spotting talented young musicians.

  她一直有发掘年轻音乐天才的敏锐眼光。

• piercing

  Piercing suggests a look, question, or mind that seems to see through surfaces to the truth, often with a slightly intense or unsettling effect on the person being observed.

  piercing 形容一种眼神、问题或头脑，仿佛能看穿表象、直达真相，往往会给被观察者带来一种强烈甚至令人不安的感觉。

  The professor's piercing questions revealed the flaws in our argument immediately.

  教授犀利的问题立刻揭露了我们论证中的漏洞。

Acute, keen and piercing describe a sharp sense or mind, but the tone differs. Acute is formal, stressing intensity of feeling or careful attention. Keen is everyday, a naturally sharp or skilled eye or mind. Piercing suggests a look that sees through to the truth.

这三个词都可以表示“敏锐、尖锐”，但语气和使用场合不同：acute 偏正式或专业，强调强度；keen 是日常常用词，强调天赋或热情；piercing 则强调看穿表象、直指本质，语气较强烈。这里不比较 keen 表示“渴望的，热衷的”（如 keen on doing something）和 piercing 表示“尖锐刺耳的（声音）”（如 a piercing scream）这两个义项。

Compared meaning: very strong (a feeling or reaction) (adjective).

比较义项：强烈的（感觉、情绪等的强烈程度）（形容词）。

• keen 本词

  Keen describes a strongly felt, usually positive interest, desire or sharpened sense; it often appears in the pattern 'keen on' plus a noun or gerund, and suits formal or literary contexts more than strong.

  keen表示强烈且通常是积极的兴趣、渴望或敏锐的感官，常用“keen on+名词/动名词”结构，语体比strong更正式或书面化。

  My father is keen on gardening and spends every weekend outside.

  我父亲对园艺有着强烈的兴趣，每个周末都待在户外。

• strong

  Strong is the neutral, all-purpose word for intensity, fitting almost any strongly felt sensation, opinion, smell or taste without special connotation, making it the safest everyday choice.

  strong是表达强烈程度最中性、最通用的词，几乎适用于任何强烈的感觉、意见、气味或味道，没有特殊的感情色彩，是日常生活中最安全的选择。

  The soup had a strong garlic flavor that lingered for hours.

  这汤有很强烈的大蒜味，久久不散。

• violent

  Violent implies an extreme, sudden intensity that feels uncontrolled or forceful, usually describing negative reactions like anger, storms or pain rather than calm interests or desires.

  violent暗示一种极端、突然、显得失控且带有冲击力的强烈程度，通常用于描述愤怒、风暴或疼痛等负面反应，而不是平静的兴趣或渴望。

  His violent temper made everyone in the office afraid to speak up.

  他猛烈的脾气让办公室里的每个人都不敢说话。

Keen, strong, and violent all describe strong feelings or reactions. Keen describes a positive interest, desire, or sharp sense. Strong is the neutral, all-purpose word for almost any strong feeling, smell, or taste. Violent means extreme and uncontrolled, usually describing negative reactions like anger.

这三个词都可以形容感觉、情绪或反应的“强烈”，但语气和搭配不同：keen多用于积极的兴趣、渴望或敏锐的感官，常用“keen on”结构；strong是最常用、最中性的说法，几乎能修饰任何强烈的感觉或味道；violent语气最强，常带负面、失控的意味，多用于愤怒、风暴等剧烈反应。这里不比较keen表示“锋利的、热衷的”、strong表示“强壮的、坚固的”，也不比较violent表示“使用暴力的、猛烈打击的”这些其他义项。