二 èr — two; second — Jiǎoluò Shūwū

二 simplified · traditional · same

èr

two · second · duality

HSK 1 笔画 2 部首二 (two) 声调第四声 (falling)

笔顺 bǐshùn · Stroke order

Click the character to replay. Press Try drawing to write it yourself.

字源 zìyuán Etymology & Structure

字源洞见 zìyuán dòngjiàn · Etymological Insight

二 èr is a purely indicative character: two horizontal strokes instantiate the number by showing it. There is no pictographic origin and no semantic component to decode. The oracle bone form shows two horizontal lines of roughly equal weight. In some bronze inscriptions the top stroke is slightly shorter than the bottom, a subtle encoding of hierarchy: the upper is lesser, the lower is greater. The written form has remained almost unchanged for three thousand years.

Unlike the characters for "one" 一 and "three" 三, which also use stacked strokes, 二 carries the specific philosophical weight of the first split: the moment unity divides and opposition begins. This is not a later accretion; the character's role in cosmological texts predates most of the literary tradition.

二 serves as the second Heavenly Stem marker in the calendrical system, where 乙 yǐ (also "second") is used in date-counting. The two systems run in parallel across classical Chinese administrative and astronomical records.

笔顺 bǐshùn Formation, Strokes & Radical

笔顺 bǐshùn · Stroke Order Two strokes, both horizontal. Written left to right, top before bottom. The top stroke is shorter; the bottom stroke is longer. There are no diagonal or vertical strokes. Total stroke count: 2.

部首功能 bùshǒu gōngnéng · 二 as a Radical 二 is both a standalone numeral and the Kangxi radical #7. It contributes a "two / duality / layered" semantic element to characters built on it. Characters sharing this radical include: 元 yuán (origin; primary; dollar) — two strokes above 儿, suggesting primacy above all else; 亘 gèn (to extend across; perpetual) — 二 above 日, spanning from horizon to horizon; 互 hù (mutual; reciprocal) — two interlocking horizontal elements suggesting exchange; 井 jǐng (well; orderly grid) — originally the grid shape of a water well, classified under 二 in some systems.

词汇 cíhuì Key Compounds

辨析 biànxī · 二 vs. 两 — The Essential Distinction

Both 二 èr and 两 liǎng mean "two," but they are not interchangeable. 二 èr is used in counting sequences (一、二、三…), arithmetic (二加二等于四), ordinal compounds (第二 dì-èr "second"), and positions in a series (二月 Èryuè "February"). 两 liǎng is used before measure words when specifying a quantity of something: 两个人 liǎng gè rén "two people," 两本书 liǎng běn shū "two books." Using 二 before a measure word sounds unnatural in standard Mandarin, except in certain fixed expressions and regional varieties. This distinction trips learners at every level.

二手 èrshǒu second-hand; used; pre-owned

Adj 形容词 xíngróngcí

二 èr (two; second) + 手 shǒu (hand). Something that has passed through a second hand. Standard term for used goods, pre-owned vehicles, and resale markets.

我在二手市场买了一辆自行车。

Wǒ zài èrshǒu shìchǎng mǎi le yī liàng zìxíngchē.

I bought a bicycle at the second-hand market.

二手烟对健康有害。

Èrshǒu yān duì jiànkāng yǒu hài.

Second-hand smoke is harmful to health.

第二 dì-èr second; the second (ordinal)

Adj 形容词 xíngróngcí

第 dì (ordinal prefix) + 二 èr. The prefix 第 converts any cardinal number into an ordinal. 第二 is how Chinese renders "second" in rankings, chapters, floors, and sequences.

她在比赛中获得了第二名。

Tā zài bǐsài zhōng huòdé le dì-èr míng.

She came second in the competition.

语法 yǔfǎ · Grammar Note The 第 + number pattern works across all cardinals: 第一 (first), 第三 (third), 第十 (tenth). For months and dates, 第 is dropped: 二月 (February), not 第二月.

二月 Èryuè February; the second month

N 名词 míngcí

二 èr (two) + 月 yuè (moon; month). Chinese months are purely positional: the first month is 一月, the second is 二月, through 十二月 (December). There are no separate month names.

春节通常在一月或二月。

Chūnjié tōngcháng zài yīyuè huò èryuè.

Spring Festival usually falls in January or February.

二胡 èrhú erhu; two-stringed bowed fiddle

N 名词 míngcí

二 èr (two) + 胡 hú (a category of instruments of non-Han origin, literally "barbarian"). The erhu has exactly two strings, which defines both its name and its voice: the two strings produce the characteristic close-interval resonance that makes the instrument sound like a human throat. The instrument reached its classical form by the Song dynasty (960–1279 CE) and remains the signature melodic voice of Chinese classical ensembles.

二胡的声音非常动人。

Èrhú de shēngyīn fēicháng dòngrén.

The sound of the erhu is deeply moving.

二话 èrhuà a second word; objection; demurral

N 名词 míngcí

二 èr (two; a second) + 话 huà (speech; words). Always appears in the negative: 没有二话 or 不说二话 means to comply without objection or complaint, without a second word.

他二话没说，立刻帮了忙。

Tā èrhuà méi shuō, lìkè bāng le máng.

Without a word of objection, he helped immediately.

十二 shí'èr twelve

N 名词 míngcí

十 shí (ten) + 二 èr (two). The separator apostrophe in pinyin marks the syllable boundary: shí·èr, not shí·ér. Twelve is culturally loaded: 十二生肖 shí'èr shēngxiào (the twelve zodiac animals) and 十二个月 shí'èr gè yuè (twelve months) both run on this number.

十二生肖是中国文化的重要符号。

Shí'èr shēngxiào shì Zhōngguó wénhuà de zhòngyào fúhào.

The twelve zodiac animals are an important symbol of Chinese culture.

二元论 èryuánlùn dualism; dualist philosophy

N 名词 míngcí

二 èr (two) + 元 yuán (origin; element; primary unit) + 论 lùn (theory; discourse). The philosophical position that reality is composed of two irreducible substances or principles. 二元 èryuán alone means "dual; binary; two-dimensional" and appears across technical and philosophical contexts.

笛卡尔的哲学是一种二元论。

Díkǎ'ěr de zhéxué shì yī zhǒng èryuánlùn.

Descartes' philosophy is a form of dualism.

二元 èryuán Two in Chinese Cosmology

宇宙论 yǔzhòulùn · Cosmological Insight

In Chinese cosmological thought, two is not a neutral quantity. It is the first meaningful number: the moment unity breaks into opposition. The Daodejing (道德经), attributed to Laozi and compiled no later than the 4th century BCE, states in chapter 42:

道生一，一生二，二生三，三生万物。
Dào shēng yī, yī shēng èr, èr shēng sān, sān shēng wànwù.

The Dao generates One. One generates Two. Two generates Three. Three generates the ten thousand things.

Two here is the moment duality splits from unity: yin 阴 and yang 阳, the two complementary forces. Their interaction produces Three — the dynamic tension from which everything proceeds. The entire 64-hexagram system of the Yijing (易经, Book of Changes) is derived from the binary opposition of a solid line (yang, ⚊) and a broken line (yin, ⚋). Every hexagram is a six-line arrangement of just these two elements. The mathematics of two generates the whole.

This framing means 二 carries a cosmological charge that "two" in English does not. When a Chinese classical text uses 二, the resonance of the yin-yang split is not far beneath the surface.

文化语境 wénhuà yǔjìng · Number Culture Even numbers and luck: Chinese number culture generally treats even numbers as auspicious because 双 shuāng (double; paired) connotes good fortune. Two is the smallest even number and structurally paired with 双. Gifts, red envelopes, and wedding arrangements favor even quantities.

二 vs. 两 in everyday use: On a bus, you ask for 两张票 liǎng zhāng piào (two tickets). In arithmetic, you say 一加一等于二 (one plus one equals two). On a floor directory, you look for 二楼 (the second floor). The contexts are non-overlapping once internalized.

成语 chéngyǔ Idioms & Set Phrases

三心二意 sān xīn èr yì three hearts, two minds — indecisive; half-hearted; wavering Lit: three-heart-two-mind. The image of a person whose attention and commitment are split across multiple directions. Used to criticize someone who cannot commit: 你不能三心二意，要专心！ Nǐ bù néng sān xīn èr yì, yào zhuānxīn! "Stop being half-hearted — be focused!" The opposite ideal is 专心致志 zhuānxīn zhì zhì (single-minded and wholehearted).

一石二鸟 yī shí èr niǎo one stone, two birds — accomplish two goals with a single action The Chinese and English idioms are structurally identical. The image of a single stone bringing down two birds appears to have developed independently in both traditions, though the Chinese form likely circulated in literary Chinese before modern contact. In use: 这个方案真是一石二鸟。Zhège fāng'àn zhēn shì yī shí èr niǎo. "This plan is a real two-birds-one-stone solution."

二虎相争 èr hǔ xiāng zhēng two tigers fight — when two powerful forces clash, both suffer The full form is often 两虎相争，必有一伤 liǎng hǔ xiāng zhēng, bì yǒu yī shāng: "when two tigers fight, one is certain to be wounded." Used to counsel against unnecessary conflict between equals, and to describe political or commercial battles where both sides bleed. The image appears in Shiji (史记), Sima Qian's Records of the Grand Historian, completed c. 94 BCE.

说一不二 shuō yī bù èr say one, not two — a person whose word is final; absolute authority Lit: say-one-not-two. To speak once and have it stand; not to be contradicted. Describes a figure of absolute authority within their domain. Can be used admiringly (a decisive leader) or critically (an autocrat). 他在公司里说一不二。Tā zài gōngsī lǐ shuō yī bù èr. "In the company, what he says goes."

记忆法 jìyìfǎ · Retention Image

Two strokes: the first is the Dao, undivided. The second stroke breaks away below it, and now there are two. Between the two lines, the gap is not empty — it is the space where yin and yang hold each other apart. Every character in the language was eventually written with a brush held in a hand that learned to count with these two lines first.