The very first measure word most learners meet is 只 (zhī) — 一只猫 (a cat), 一只狗 (a dog). So it comes as a shock when the same word is wrong for a horse, a cow, or a fish. Animals don't share one classifier in Chinese; they're sorted by shape and size, and there are five words you need to know.
大多数学习者最先遇到的量词是"只 (zhī)"——一只猫、一只狗。所以当你发现同一个字用在马、牛、鱼身上竟然错了，会大吃一惊。中文里动物不共用一个量词；它们按体型和大小分类，你一共需要记住五个字。
The five animal measure words at a glance（五种动物量词一览）
- 只 (zhī) — small animals, birds, pets · 一只猫 (a cat), 一只鸟 (a bird)
- 头 (tóu) — large livestock · 一头牛 (a cow), 一头猪 (a pig)
- 匹 (pǐ) — horses (and mules) · 一匹马 (a horse)
- 条 (tiáo) — long, flexible creatures · 一条鱼 (a fish), 一条蛇 (a snake)
- 窝 (wō) — a whole litter / brood · 一窝小狗 (a litter of puppies)
- 只 (zhī) —— 小动物、鸟类、宠物 · 一只猫、一只鸟
- 头 (tóu) —— 大型家畜 · 一头牛、一头猪
- 匹 (pǐ) —— 马（及骡子）· 一匹马
- 条 (tiáo) —— 细长、柔软的动物 · 一条鱼、一条蛇
- 窝 (wō) —— 一窝（整窝幼崽）· 一窝小狗
If you want the fast rule, that list is it — and our 只 / 头 / 匹 comparison is built for exactly the moment when two of them seem to overlap. The rest of this guide explains the logic, so the right word starts to feel obvious.
如果你只想要速记规则，上面这张表就够了——而我们的只 / 头 / 匹 对比页 正是为两个量词"打架"的时刻准备的。本指南其余部分解释背后的逻辑，让正确的字逐渐变得理所当然。
只 — the small-animal default（只——小动物默认量词）
只 started life as a word for a single bird, then spread to anything small, single and animal-like: 一只猫, 一只狗, 一只老鼠 (a mouse), 一只鸡 (a chicken). When in doubt about a small animal, 只 is almost always safe.
Its one big limit: 只 does not scale up. A cow, a horse or an elephant is too large and too "counted by the head" for 只 to fit. Open the full card for 只 (zhī) for more examples.
"只"最初指单只的鸟，后来扩展到任何小巧、单独、像动物的东西：一只猫、一只狗、一只老鼠、一只鸡。拿不准小动物时，用"只"几乎总是安全。
它的一大局限：只不往上扩。牛、马、大象太大，又太"按头数"，"只"就装不下了。打开只 (zhī) 详情卡看更多例子。
头 — literally "counted by the head"（头——字面意思"按头数"）
头 means "head", and that's the whole idea: large livestock are counted by the head. 一头牛 (a cow), 一头猪 (a pig), 一头大象 (an elephant), 一头驴 (a donkey).
The rule of thumb: if the animal is big enough that a farmer would tally it "per head", it takes 头. Small enough to hold, and it's back to 只. See 头 (tóu).
"头"就是"脑袋"，道理全在这：大型家畜按头数。一头牛、一头猪、一头大象、一头驴。
经验法则：如果动物大到农夫会"按头"清点，就用"头"；小到能捧在手里，就回到"只"。见头 (tóu)。
匹 — horses, and only horses（匹——马，且仅马）
Horses break every animal rule — they take 匹 (pǐ), the same word for a bolt of cloth. The short version: 匹 once meant a matched pair, and a horse's original job was to be one half of a well-matched team pulling a carriage. That history is worth its own read — we tell it in why a horse is 一匹马 and not 一只马. For the card itself, see 匹 (pǐ).
马打破了所有动物规则——它们用"匹 (pǐ)"，也就是量布的那个"匹"。简言之：匹曾经指"一对"，而马的本分，原是拉车的成对队伍里那一半。这段历史值得单写一篇——我们在为什么是"一匹马"而非"一只马" 里讲过。量词卡本身见匹 (pǐ)。
条 — long and flexible（条——细长而柔软）
条 is the "long things" measure word, and it doesn't care whether the long thing is alive: 一条鱼 (a fish), 一条蛇 (a snake), but also 一条路 (a road), 一条河 (a river), 一条裤子 (a pair of pants). If a creature is elongated like a rope, it takes 条. See 条 (tiáo).
"条"是"长条物"的量词，并且不在乎这长条物是不是活的：一条鱼、一条蛇，也包括一条路、一条河、一条裤子。如果某个生灵像绳子一样细长，就用"条"。见条 (tiáo)。
窝 — counting the whole family（窝——数整窝）
窝 (wō) means "nest", and it counts an entire litter or brood born together: 一窝小狗 (a litter of puppies), 一窝小鸟 (a brood of chicks), 一窝蜜蜂 (a swarm of bees). It's not about one animal — it's about the group that shares a nest. See 窝 (wō).
"窝 (wō)"是"巢"，数的是一窝同时出生的幼崽：一窝小狗、一窝小鸟、一窝蜜蜂。它数的不是一只动物——而是共享一个巢的那一群。见窝 (wō)。
The shape logic that ties it together（串起一切的形状逻辑）
Every one of these is a fossil of how Chinese speakers once thought about animals:
- small → 只 · large livestock → 头 · horse → 匹 · long → 条 · whole nest → 窝
Learn the shape, not the animal, and the "irregular" cases stop being irregular.
这些字每一个，都是古人如何看待动物的化石：
- 小 → 只 · 大型家畜 → 头 · 马 → 匹 · 细长 → 条 · 整窝 → 窝
学的是形状，不是动物；这样"不规则"的情况就不再不规则。
One animal, several answers（一个动物，多种答案）
Some nouns legitimately take more than one measure word, depending on what you're counting. Our reverse noun index shows the full list for hundreds of nouns — try horse, fish, cat or elephant and you'll see every measure word that goes with each.
有些名词确实可以搭配多个量词，取决于你数的是什么。我们的反向名词索引 给出了数百个名词的完整清单——试试马、鱼、猫 或大象，你会看到每个名词搭配的所有量词。
Put it into practice（动手练练）
Reading the rule is step one. Step two is drilling it until it's automatic — try the animal measure words comparison, then test yourself with our interactive quiz.