Vocabulary · 词汇 cíhuì

知道

zhīdào

The everyday verb for knowing a fact: how to say you know or don't know something, the all-purpose 知道了 acknowledgement, and how it differs from knowing a person or truly understanding.

~4 min read

字源 zìyuán Etymology & Structure

字源洞见 zìyuán dòngjiàn · Etymological Insight

知 zhī (to know) joins 矢 shǐ (arrow) and 口 kǒu (mouth): knowledge as words that fly straight and swift to their mark, the arrow-like directness of someone who knows and can say. 道 dào here contributes its sense of "way, path, to say," and in this compound functions as a verbal complement, so 知道 reads as "to know the way of it," to have the matter clear.

The single character 知 already means "to know" and is the form used in classical and literary Chinese (知己 a friend who knows you, 知识 knowledge, 知行合一 the unity of knowing and acting). In modern spoken Chinese the disyllabic 知道 is the ordinary verb. The pairing with 道 is worth noting: the same 道 that means "the Way" in philosophy here simply helps build the everyday word for knowing a fact.

知道 zhīdào The Core Verb

知道 zhīdào to know (a fact); to be aware that

V 动词 dòngcí

To know a fact, a piece of information, or that something is the case. It commonly takes a clause as its object (我知道他来了, I know he came) or a noun (我知道答案, I know the answer). The second syllable is often pronounced in neutral tone in fast speech (zhīdao). This is "know that," not "know a person" (认识) or "understand deeply" (了解).

我知道你的意思。

Wǒ zhīdào nǐ de yìsi.

I know what you mean.

你知道他在哪儿吗？

Nǐ zhīdào tā zài nǎr ma?

Do you know where he is?

我不知道这件事。

Wǒ bù zhīdào zhè jiàn shì.

I didn't know about this.

用法 yòngfǎ Patterns — Objects, Negation, 知道了

知道 in use · the core patterns Subject + 知道 + Clause , 我知道他是老师 · I know he is a teacher
Subject + 不知道 + Object , 我不知道 · I don't know
Subject + 知道 + Question word + 吗 , 你知道怎么去吗？· Do you know how to get there?
知道了 , got it; understood (acknowledgement)
谁知道 / 不知道… , who knows…; one wonders…

知道了 zhīdào le got it; understood; okay

The everyday acknowledgement that you have received and registered information or an instruction. Extremely common as a one-word reply. Beware the tone: a flat or clipped 知道了 can read as impatient, like "yeah, I know already." 好的 (okay) or 明白了 (understood) are gentler alternatives.

「记得带伞。」「知道了。」

"Jìde dài sǎn." "Zhīdào le."

"Remember to bring an umbrella." "Got it."

不知道 bù zhīdào to not know

Negated with 不, never 没 (没知道 is wrong). It covers both "I don't know" and "I didn't know," since Chinese marks tense by context, not by changing the verb. 谁知道 ("who knows") and 不知道为什么 ("for some reason, who knows why") are common fixed uses.

我也不知道为什么。

Wǒ yě bù zhīdào wèishénme.

I don't know why either.

辨析 biànxī Three Ways to Know

辨析 biànxī · Distinguishing the Words

English "to know" splits into three different Chinese verbs, and choosing the wrong one is a classic learner error. 知道 zhīdào is to know a fact or to know of something: 我知道这家餐厅 ("I know that restaurant exists, I know about it"). 认识 rènshi is to be personally acquainted, to recognise: 我认识他 ("I know him, we've met"). 了解 liǎojiě is to understand thoroughly: 我很了解他 ("I understand him well, I know him deeply").

The distinctions matter. You can 知道 a celebrity (know who they are) without 认识 them (having met). You might 认识 a coworker for years before you 了解 them (truly understand who they are). For knowing a place, 知道 means knowing it exists; for knowing a language or skill, neither of these fits and you use 会 huì (我会说中文, I can speak Chinese). Match the verb to the kind of knowing.

成语 chéngyǔ Set Phrases

知之为知之，不知为不知。 zhī zhī wéi zhī zhī, bù zhī wéi bù zhī. To know what you know and know what you don't know — that is real knowledge. From the Analects of Confucius. The full saying ends 是知也 ("this is wisdom"). It teaches intellectual honesty: genuine knowledge includes a clear sense of the limits of one's knowledge. One of the most quoted lines in Chinese on the nature of knowing, and a reminder that admitting 不知道 is itself a kind of wisdom.

知己知彼 zhī jǐ zhī bǐ know yourself and know the other From the Art of War: 知己知彼，百战不殆 ("know yourself and know the enemy, and in a hundred battles you will never be in peril"). Here 知 is the classical single-character "to know." The chengyu is used for any situation requiring thorough knowledge of both one's own position and the other side's, in competition, negotiation, or strategy.

众所周知 zhòng suǒ zhōu zhī as everyone knows; it is common knowledge A formal phrase, literally "what the crowd all knows," used to introduce a widely accepted fact. 众 (the masses) + 周知 (universally known). Common in writing and speeches as a way of appealing to shared knowledge, the Chinese equivalent of "as is well known."