3 + 3 → 2 + 3
Third tone sandhi
Two 3rd tones in a row: say the first one rising. The pinyin still shows two 3rd tones.
你好 nǐ hǎo · hello
Three in a row? Group the words first: 展览馆 (zhǎnlǎnguǎn) 2 + 2 + 3, 我很好 (wǒ hěn hǎo) 3 + 2 + 3.
Mandarin Tone Sandhi Rules
Some tones change when words meet. Here are the four changes, with audio. Then check any phrase.
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The four tone changes, with audio
yī → yí before a 4th · yì before others
一 (yī) tone change
On its own it is yī. 一个 (yí gè), but 一天 (yì tiān).
一个 yí gè · one (of something)
Stays yī when counting, in dates, and in 第一 (dì yī). 一 (yī) in the dictionary
bù → bú before a 4th
不 (bù) tone change
Before other tones it stays bù.
不是 bú shì · is not
Goes light in 好不好 (hǎo bu hǎo) and 对不起 (duìbuqǐ). 不 (bù) in the dictionary
3 + 1/2/4 → low 3
Half third tone
Before any other tone, a 3rd tone stays low and doesn't rise.
好吃 hǎochī · tasty
The full dip-and-rise is only for a word said alone. Check yours in the Tone Checker
Why the pinyin doesn't change: Dictionaries write each character's original tone. China's official pinyin rules (GB/T 16159-2012, §6.5.2) let teaching materials write the changed tone for 一 (yī) and 不 (bù) only. So this page writes yí gè and bú shì, but always nǐ hǎo.
Tone sandhi checker
Type or paste up to 120 characters of simplified Chinese. The checker marks each syllable that changes, says why, and plays the phrase. It reads text only and never records you.
你好 nǐ hǎo
- 你 (nǐ) rises before 好 (hǎo), another 3rd tone.
Examples and exceptions
Tone sandhi, 变调 (biàndiào), means a Mandarin tone changes because of the syllable next to it. The characters and their dictionary tones stay the same. Only the way you say them changes. Four patterns cover almost everything a learner hears.
1. Third tone sandhi: 3 + 3 → 2 + 3
When two third tones meet, say the first one as a rising second tone. 你好 (nǐ hǎo) keeps both third-tone marks, but 你 (nǐ) rises, so the phrase sounds like ní hǎo. The same happens in 很好 (hěn hǎo), 可以 (kěyǐ) and 水果 (shuǐguǒ). With three or more in a row, group the words first and apply the rule inside each group. 展览馆 (zhǎnlǎnguǎn) is said 2 + 2 + 3. 我很好 (wǒ hěn hǎo) groups as wǒ + hěn hǎo, so it is usually 3 + 2 + 3.
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 你好 | nǐ hǎo | hello | 你 (nǐ) rises |
| 很好 | hěn hǎo | very good | 很 (hěn) rises |
| 可以 | kěyǐ | can, may | 可 (kě) rises |
| 老虎 | lǎohǔ | tiger | 老 (lǎo) rises |
| 水果 | shuǐguǒ | fruit | 水 (shuǐ) rises |
| 雨伞 | yǔsǎn | umbrella | 雨 (yǔ) rises |
| 手表 | shǒubiǎo | wristwatch | 手 (shǒu) rises |
| 洗澡 | xǐzǎo | take a shower | 洗 (xǐ) rises |
| 打扫 | dǎsǎo | tidy up | 打 (dǎ) rises |
| 几点 | jǐ diǎn | what time | 几 (jǐ) rises |
| 好久 | hǎojiǔ | a long time | 好 (hǎo) rises |
| 小狗 | xiǎogǒu | puppy | 小 (xiǎo) rises |
| 米酒 | mǐjiǔ | rice wine | 米 (mǐ) rises |
| 网友 | wǎngyǒu | online friend | 网 (wǎng) rises |
Three in a row
Group the words first, then apply the rule inside each group.
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 展览馆 | zhǎnlǎnguǎn | exhibition hall | 展 (zhǎn) and 览 (lǎn) rise: it is one word |
| 我很好 | wǒ hěn hǎo | I'm fine | 很 (hěn) rises; 我 (wǒ) usually stays low (wǒ + hěn hǎo) |
| 小雨伞 | xiǎo yǔsǎn | little umbrella | 雨 (yǔ) rises; 小 (xiǎo) usually stays low (xiǎo + yǔsǎn) |
2. 一 (yī): yí before a 4th tone, yì before the others
On its own, 一 (yī) keeps its first tone. Before a fourth tone it becomes yí: 一个 (yí gè), 一下 (yíxià). Before a first, second or third tone it becomes yì: 一天 (yì tiān), 一年 (yì nián), 一起 (yìqǐ). It stays yī when you count, in numbers and dates, in 第一 (dì yī), and at the end of a word, as in 十一 (shíyī). Between a repeated verb it goes light: 看一看 (kàn yi kàn).
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 一个 | yí gè | one (of something) | yí before a 4th tone |
| 一样 | yíyàng | the same | yí before a 4th tone |
| 一下 | yíxià | for a moment | yí before a 4th tone |
| 一半 | yíbàn | a half | yí before a 4th tone |
| 一共 | yígòng | altogether | yí before a 4th tone |
| 一块钱 | yí kuài qián | one yuan | yí before a 4th tone |
| 一天 | yì tiān | one day | yì before a 1st tone |
| 一杯 | yì bēi | one cup | yì before a 1st tone |
| 一年 | yì nián | one year | yì before a 2nd tone |
| 一直 | yìzhí | all along | yì before a 2nd tone |
| 一起 | yìqǐ | together | yì before a 3rd tone |
| 一点 | yìdiǎn | a little | yì before a 3rd tone |
| 一百 | yìbǎi | one hundred | yì before a 3rd tone |
| 看一看 | kàn yi kàn | have a quick look | light between a repeated verb |
| 想一想 | xiǎng yi xiǎng | think it over | light between a repeated verb |
When it doesn't change
一 (yī) keeps its first tone when it is a number rather than an amount. 一 (yī) in the dictionary
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 第一 | dì yī | first | an ordinal |
| 十一 | shíyī | eleven | the last syllable |
| 一月 | yīyuè | January | a date |
| 星期一 | xīngqīyī | Monday | a date |
3. 不 (bù): bú before a 4th tone
不 (bù) is a fourth tone, except before another fourth tone, where it rises to bú: 不是 (bú shì), 不要 (bú yào), 不对 (bú duì). Before other tones it stays bù: 不吃 (bù chī), 不来 (bù lái), 不好 (bù hǎo). In questions like 好不好 (hǎo bu hǎo), and in 对不起 (duìbuqǐ), it is light.
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 不是 | bú shì | is not | bú before a 4th tone |
| 不要 | bú yào | don't | bú before a 4th tone |
| 不对 | bú duì | not right | bú before a 4th tone |
| 不错 | búcuò | not bad, pretty good | bú before a 4th tone |
| 不去 | bú qù | not going | bú before a 4th tone |
| 不会 | bú huì | can't, won't | bú before a 4th tone |
| 不用 | búyòng | no need | bú before a 4th tone |
| 不太好 | bú tài hǎo | not so good | bú before a 4th tone |
| 好不好 | hǎo bu hǎo | OK? | light in a yes-or-no question |
| 是不是 | shì bu shì | is it or isn't it? | light in a yes-or-no question |
| 对不起 | duìbuqǐ | sorry | light in a set phrase |
| 差不多 | chàbuduō | about the same | light in a set phrase |
| 看不见 | kàn bu jiàn | can't see | light in “can't + verb” |
| 跑不动 | pǎo bu dòng | too tired to run | light in “can't + verb” |
When it doesn't change
Before a first, second or third tone, 不 (bù) does not change. 不 (bù) in the dictionary
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 不吃 | bù chī | not eating | before a 1st tone |
| 不忙 | bù máng | not busy | before a 2nd tone |
| 不来 | bù lái | not coming | before a 2nd tone |
| 不好 | bù hǎo | not good | before a 3rd tone |
| 不冷 | bù lěng | not cold | before a 3rd tone |
4. The half third tone
Before any other tone, a third tone stays low and does not rise back up: 好吃 (hǎochī), 老师 (lǎoshī), 请问 (qǐngwèn). You hear the full dip-and-rise only when the syllable is said alone or ends a phrase.
| Chinese | Pinyin | English | What happens |
|---|---|---|---|
| 好吃 | hǎochī | tasty | 好 (hǎo) stays low before a 1st tone |
| 好人 | hǎorén | a good person | 好 (hǎo) stays low before a 2nd tone |
| 好看 | hǎokàn | good-looking | 好 (hǎo) stays low before a 4th tone |
| 老师 | lǎoshī | teacher | 老 (lǎo) stays low before a 1st tone |
| 请问 | qǐngwèn | excuse me | 请 (qǐng) stays low before a 4th tone |
| 你们 | nǐmen | you (plural) | 你 (nǐ) stays low before a light syllable |
Print or save
Download the rules (PDF): 5 pages: one rule per page, with examples and a self-check.
Tone Changes in Everyday Mandarin: a free printable PDF, 24 pages.
Common questions
When does 不 (bù) change to bú?
Only before a fourth tone: 不是 (bú shì), 不要 (bú yào), 不对 (bú duì). Before first, second and third tones it stays bù, as in 不吃 (bù chī), 不忙 (bù máng) and 不好 (bù hǎo). In yes-or-no questions like 好不好 (hǎo bu hǎo) and set phrases like 对不起 (duìbuqǐ), it is usually light and neutral.
What is tone sandhi in Mandarin?
Tone sandhi, 变调 (biàndiào), is a tone change caused by the syllable next to it. Beginners need three rules: two third tones in a row, where the first rises; 一 (yī), which changes with the tone after it; and 不 (bù), which rises before a fourth tone. Pinyin usually keeps the dictionary tones, so you apply the changes when you speak.
What is the third-tone sandhi rule?
When two third tones meet, the first is said as a rising second tone: 你好 (nǐ hǎo) sounds like ní hǎo, and 很好 (hěn hǎo) like hén hǎo. The rise always lands on the first syllable, so 老李 (Lǎo Lǐ) is said Láo Lǐ, never Lǎo Lí. The second syllable keeps its third tone.
What is the 3-3-3 rule in Mandarin?
It is what happens when three third tones meet, and the answer depends on how the words group. 展览馆 (zhǎnlǎnguǎn, exhibition hall) is one word, so the first two rise: it sounds like zhán lán guǎn. 我很好 (wǒ hěn hǎo, I'm fine) groups as 我 (wǒ) + 很好 (hěn hǎo), so it usually sounds like wǒ hén hǎo, though fast speech can give wó hén hǎo.
When does 一 (yī) change tone?
一 (yī) is said yí before a fourth tone, as in 一个 (yí gè) and 一样 (yíyàng), and yì before a first, second or third tone, as in 一天 (yì tiān), 一年 (yì nián) and 一起 (yìqǐ). It keeps yī when you count, at the end of a word such as 十一 (shíyī), in ordinals like 第一 (dì yī) and in dates like 一月 (yīyuè).
Should I write tone sandhi changes in pinyin?
Not for third tones: standard pinyin keeps each syllable's dictionary tone, so 你好 (nǐ hǎo) keeps both third-tone marks even though it sounds like ní hǎo. For 一 (yī) and 不 (bù), China's pinyin spelling standard, GB/T 16159-2012, also writes the original tone but lets teaching materials mark the change, which is why many textbooks write 一个 (yí gè) with the changed tone.
Does the tone sandhi checker listen to my pronunciation?
No. Type or paste up to 120 characters of simplified Chinese and it shows the dictionary pinyin, the spoken pinyin with each change highlighted, and audio of the phrase; it never records you. To compare your own voice with a target tone, use the free Tone Checker, or practice in conversation with Mei Lin, SayMei's AI tutor. Your first lesson is free.
Keep going
Type any phrase into the checker to see which syllables change and why, then listen to it. For a longer text, the Chinese to Pinyin converter writes the 一 (yī) and 不 (bù) changes for you. For paper practice, get the free Tone Changes in Everyday Mandarin PDF.
Tones Chart & Tone Pairs · Practice connected speech · Pinyin Chart