Chengyu: should you learn Chinese idioms?

Kungfucius once answered this question with "Nope! Stop learning chéngyǔ!" and then used half a dozen of them to make the point. The position has matured a little. You should learn 成語 (成语) chéngyǔ, but later than most textbooks suggest, fewer than most lists offer, and from real sentences instead of from tables like the one below.

The short version: as a beginner, ignore them. From intermediate level, collect the ones you keep meeting. Use them yourself only when you have heard a native speaker use them in the same kind of sentence.

What is a chengyu?

A chéngyǔ is a fixed expression, nearly always four characters long, that behaves like a single word. The name means "ready-made phrase". You cannot swap a character or change the order, and the meaning is often more than the sum of the parts.

Most come from classical literature: the philosophers, the early histories, poetry, and later the great novels. Many are therefore two thousand years old or more, and they keep the compressed grammar of Classical Chinese. That is the charm and the difficulty. A translation is not enough, because the phrase is the punchline of a story or a quotation you are expected to know.

A few are young. 一箭雙鵰 (一箭双雕) yí jiàn shuāng diāo, "one arrow, two eagles", is the classical way to kill two birds with one stone, taken from an anecdote in the History of the Northern Dynasties about a general who shot two eagles fighting over a piece of meat. The plainer 一石二鳥 (一石二鸟) yì shí èr niǎo, "one stone, two birds", is no ancient wisdom at all: it is the English proverb, translated in Japan and borrowed into Chinese from there. Kungfucius prefers the arrow, for the decisiveness.

Japanese and Korean have the same four-character habit, called 四字熟語 yojijukugo and 사자성어 sajaseongeo. Many of their idioms are shared with Chinese, and some are home-grown.

Chéngyǔ are also not the only kind of idiom. Colloquial three-character phrases such as those on the page about Chinese eating idioms are a separate, more relaxed family.

How many chengyu are there, and how many do Chinese people know?

It depends on who is counting. The idiom dictionary of Taiwan's Ministry of Education has about 5,000 idioms in its main section and more than 28,000 records once appendices are included. Large commercial dictionaries advertise tens of thousands.

How many a native speaker knows is not something Kungfucius has found reliably measured, so treat any precise number you read with suspicion. His own estimate: an educated adult recognises several thousand, having been drilled through twelve years of school essays and exams, and actively uses a few hundred. The gap between those two numbers is the important part. Even for natives, most chéngyǔ are reading vocabulary.

Should you learn Chinese idioms?

Yes, with three reservations that have not changed since Kungfucius first grumbled about them.

They are expensive. Learning one properly means the story, the tone and two or three example sentences. That can take the better part of an hour. In the same time you could listen to two or three podcast interviews or read a short story, and at beginner and lower intermediate level that is the better trade.

They are easy to misuse. Each chéngyǔ has a narrow range: formal or casual, praise or mockery, written or spoken. Dictionary glosses hide all of that. Use a solemn four-character phrase to describe your headache at the doctor's and you may be suspected of 胡說八道 (胡说八道) hú shuō bā dào, talking nonsense.

Daily life runs without them. You can buy vegetables, see a doctor and tell a friend about a film without a single one.

Against that stands one fact. Newspapers, speeches, novels, subtitles and educated conversation are full of them, and from upper intermediate level they are a real obstacle to understanding. The exams agree with this timing: the old HSK only leaned on chéngyǔ at Level 6, and in the lists for the new HSK they cluster in the advanced levels 7 to 9.

So the answer by level:

• Beginner: none on purpose. Learn frequent words.
• Intermediate: the everyday ones in the table below, plus any you meet three times.
• Advanced: a steady trickle from your reading, a few a week, towards a passive stock of several hundred.

You reap what you plant: 種瓜得瓜 (种瓜得瓜). Plant frequent words first and the idioms will have something to grow on.

Which chengyu should you learn first?

Not the famous fable idioms. Start with the ones that behave like ordinary vocabulary and that people say without noticing they are using an idiom. These eighteen are safe.

Chéngyǔ	Pinyin	Literal meaning	Real meaning
亂七八糟 (乱七八糟)	luàn qī bā zāo	chaos seven, mess eight	in a complete mess
莫名其妙	mò míng qí miào	nobody can name its subtlety	baffling, for no apparent reason
不可思議 (不可思议)	bù kě sī yì	cannot be thought or discussed	unbelievable, amazing
一模一樣 (一模一样)	yì mú yí yàng	one mould, one appearance	exactly alike
理所當然 (理所当然)	lǐ suǒ dāng rán	what reason requires	only natural, a matter of course
無論如何 (无论如何)	wú lùn rú hé	no matter how	in any case, whatever happens
迫不及待	pò bù jí dài	too pressed to wait	unable to wait, impatient
小心翼翼	xiǎo xīn yì yì	careful, reverent	very cautiously
恍然大悟	huǎng rán dà wù	suddenly, great realisation	to see the light at last
半途而廢 (半途而废)	bàn tú ér fèi	abandon at the halfway point	to give up halfway
三心二意	sān xīn èr yì	three hearts, two minds	half-hearted, unable to decide
人山人海	rén shān rén hǎi	people mountain, people sea	huge crowds
入鄉隨俗 (入乡随俗)	rù xiāng suí sú	enter the village, follow its customs	when in Rome, do as the Romans do
一舉兩得 (一举两得)	yì jǔ liǎng dé	one move, two gains	to achieve two things at once
一箭雙鵰 (一箭双雕)	yí jiàn shuāng diāo	one arrow, two eagles	to kill two birds with one stone
胡說八道 (胡说八道)	hú shuō bā dào	wild talk, eight ways	to talk nonsense
火上加油	huǒ shàng jiā yóu	add oil to the fire	to make a bad situation worse
種瓜得瓜 (种瓜得瓜)	zhòng guā dé guā	plant melons, get melons	you reap what you sow

The story idioms come next: 畫蛇添足 (画蛇添足), 守株待兔, 對牛彈琴 (对牛弹琴), 井底之蛙, 塞翁失馬 (塞翁失马), 自相矛盾, 亡羊補牢 (亡羊补牢) and 掩耳盜鈴 (掩耳盗铃). Every Chinese schoolchild knows them, and all eight are told in full on the page about puns and homophones, so they are not repeated here.

What is wrong with 馬馬虎虎?

馬馬虎虎 (马马虎虎) mǎmǎhǔhǔ, in relaxed speech closer to mǎmahūhū, "horse horse, tiger tiger", meaning so-so or careless, is the first idiom most foreign students learn, usually within months, because horse and tiger are early characters. Then it gets used. How are you? Mǎmǎhǔhǔ.

Kungfucius's observation over many years: learners say it weekly, and he has heard it far more often from foreigners and Chinese teachers than from native speakers in ordinary life. It is a real expression, and natives use it mostly for sloppy work, not as a reply to a greeting. For "so-so", 還好 (还好) hái hǎo or 還可以 (还可以) hái kěyǐ sound far more natural.

The lesson is general. A textbook idiom can mark you as a textbook speaker.

How native speakers actually use chengyu

• In writing, often. News headlines, opinion pieces, speeches and school essays lean on them, and pupils are rewarded for using them.
• In speech, selectively. The everyday set in the table appears all the time. The literary ones appear when someone is being witty, emphatic or slightly pompous.
• As a single unit in a sentence. 房間亂七八糟 (房间乱七八糟) fángjiān luàn qī bā zāo, "the room is a mess". 他莫名其妙地生氣了 (他莫名其妙地生气了) tā mò míng qí miào de shēngqì le, "he got angry for no reason".

The risk for learners is overuse. One well-placed chéngyǔ earns a compliment. Three in a row sounds like a recitation, and a wrong one adds oil to the fire. If in doubt, say it plainly.

How many chengyu at which level

Kungfucius's rule: pace your chengyu to your overall level.

Your level	How many	Which
Around HSK 4	5 to 10	Only the very common ones that you already hear in conversation
Around HSK 5	Add another 10	The ones that turn up in your reading and podcasts
Around HSK 6	Expand to maybe 50	The most common chengyu overall

The numbers matter less than the way you get there. Pick chengyu up naturally, through immersion and comprehensible input, when you meet them in a story, a series or a conversation. A chengyu learned from a list sounds like a list. A chengyu you have heard ten times in real life comes out at the right moment.

How to learn chengyu so they stick

1. Collect from input. When one turns up in a show, article or conversation, save the whole sentence, not the four characters alone. This is ordinary sentence mining.
2. Wait for the third meeting. An idiom you have met three times is common enough to be worth a flashcard.
3. Learn the story when there is one. A story sticks where four loose characters do not.
4. Check the register. Pleco gives example sentences, and the Ministry of Education's idiom dictionary gives sources and usage notes in Chinese.
5. Recognise first, use later. Try a new one on a teacher or language partner before taking it to a business dinner.

For this week: take the table above, mark the ones you already half know, and listen for them. They are closer than you think.