<p>I don't think there is a universal rule, but rather you just have to remember it as exceptions. Even for third tone "Liu3", it could be either /liu/ (溜, as in 你中文说得很溜) or /lio/ (六). </p>

CC BY-SA 4.0
2019-09-17T18:44:35.707Z
2019-09-17T18:44:35.707Z
strongline
<p>in Chinese Pinyin, o is prounounced as wooo,so ou can never occur, because wooou is difficult to prounounce in Chinese Pinyin. Only iu is allowed.</p>

<p>For the case ao, actually is au, but au in handwriting is apt to be confused with an, the latter occurs very frequently in Pinyin. To be distinct to an, the pronounce au is taken over by ao.</p>

CC BY-SA 4.0
2019-09-16T03:50:26.440Z
"pronounced as wooo" = pronounced as English woo? If that's what you meant, that would sound /wu/ in IPA. Pinyin letter "o" does not have that sound in general; for instance, Pinyin syllables "ao" and "dong" are pronounced /ao/ and /doŋ/ (or /dʊŋ/).
Alan Evangelista
CC BY-SA 4.0
2019-09-17T10:03:19.827Z
Nobody knows what kind of sound you're talking about by just using Latin letters without any symbol system mentioned. And it's Pinyin or PinYin, not Pinying.
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-18T12:53:27.507Z
@AlanEvangelista: I'm guessing that cauckf is talking about the pronunciation of -o by itself as a final in the syllables *bo, po, mo, fo.*
sumelic
CC BY-SA 4.0
2019-09-15T02:48:33.407Z
2019-09-19T06:10:23.417Z
2019-09-19T06:10:23.417Z
cauckf
<p>First, it is important to distinguish between the phonemic pronunciation and the phonetic pronunciation. The first represents how native speakers interpret sounds, the latter interpret how the sounds are effectively performed.</p>

<p>The Pinyin final -iu is phonemically pronounced /jəu/, not  /iou/ (reference: <a href="https://en.m.wikipedia.org/wiki/Standard_Chinese_phonology#Allophones" rel="nofollow noreferrer">https://en.m.wikipedia.org/wiki/Standard_Chinese_phonology#Allophones</a>). When combined with the Pinyin initial l-, that Pinyin final becomes the Pinyin syllable liu, phonemically pronounced /liəu/. </p>

<p>Anyway, much more important to a language learner is the phonetic pronunciation. The phonetic pronunciations of -iu may be [jəu], [jou] or even [jo̝u] (vowel O raises due to assimilation to the adjacent high sounds /j/ and /u/), which sounds similar to /ju/. The latter is the pronunciation in the audio recordings of the Pinyin syllable "liu" in the provided Pinyin table. The same also occurs in the audio recordings of the other Pinyin syllables with the final -iu.</p>

<p>Regarding the 3rd tone pronunciation of a Pinyin syllable with the final "-iu", when pronounced in isolation, it falls ([jo]) and then rises ([u]); in this way, this tone has an effect of separation and therefore tends to block the vowel assimilation that I mentioned before. That's why the [o] sound is heard in this tone and barely heard in the other tones in the audio recordings of the provided Pinyin table.</p>

CC BY-SA 4.0
2019-09-18T08:33:19.720Z
"jou" isn't even an valid syllable in PinYin. What are referring? The 韵母 iou?
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-18T08:42:29.160Z
Also notice in normal continuous speech,  3rd tone is simply low and short as other tones, it doesn't usually have a rising part. So normally, the vowel doesn't change with tones at all.
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-18T11:30:25.413Z
I had meant the Pinyin final "-iu". I have fixed it. Thanks for pointing it out.
Alan Evangelista
CC BY-SA 4.0
2019-09-17T16:30:29.803Z
2019-09-18T11:33:16.693Z
2019-09-18T11:33:16.693Z
Alan Evangelista
<p>As it is extremely hard to find a good online summary of all Pinyin pronunciation rules, I am listening the sounds in a Pinyin chart: <a href="https://chinese.yabla.com/chinese-pinyin-chart.php" rel="noreferrer">https://chinese.yabla.com/chinese-pinyin-chart.php</a> . I have read before that the final -iu is pronounced /iou/, but I can hear the "o" only in tone 3 (eg in Pinyin syllable "liu"). I am unable to hear it in tones 1 (high), 2 (rising) and 4 (falling). Is there vowel reduction in some tones or are those audios in this Pinyin chart bad?</p>

CC BY-SA 4.0
2019-09-14T00:17:18.437Z
I don't think so, because I never feel that way in Mandarin. Wha you said possible exist for third tone because sometimes 3rd tone is much longer than others, making middle part of a diphthong or triphthong much clearer
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-14T00:19:09.473Z
Most native speakers don't have the middle /o/ at all. But for a test, it might become a score point
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-14T04:54:26.927Z
Your first sentence in the first message is somewhat ambiguous and I'm not sure what you meant. You don't think that there is an extra /o/ sound in syllables with the ending -iu OR you do think that the extra sound exists, but that it does not disappears in tones 1, 2 and 4?
Alan Evangelista
CC BY-SA 4.0
2019-09-14T05:05:20.810Z
My Tone never changes my vowel.
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-14T05:10:05.670Z
Understood. And how do you pronounce Pinyin syllable "liu"? [liu] or [liou] ?
Alan Evangelista
CC BY-SA 4.0
2019-09-14T05:12:12.647Z
[liəu] or [liu]
炸鱼薯条德里克
CC BY-SA 4.0
2019-09-14T05:37:10.850Z
Why do you pronounce it in 2 different ways?
Alan Evangelista
CC BY-SA 4.0
2019-09-14T22:13:55.833Z
Related question: [Why is it written LIU in Pinyin, when there's clearly an O sound?](https://chinese.stackexchange.com/questions/993) See iopq' answer, which suggests that there can be a difference in the pronunciation of the vowel between different tones.
sumelic
CC BY-SA 4.0
2019-09-17T10:04:28.583Z
Free-variant Allophone
炸鱼薯条德里克
<pronunciation><tones>
Does pronunciation of a vowel change with tones?
# Does pronunciation of a vowel change with tones?

(Asked by: username_0 on 2019-09-14)

As it is extremely hard to find a good online summary of all Pinyin pronunciation rules, I am listening the sounds in a Pinyin chart: <https://chinese.yabla.com/chinese-pinyin-chart.php> . I have read before that the final -iu is pronounced /iou/, but I can hear the "o" only in tone 3 (eg in Pinyin syllable "liu"). I am unable to hear it in tones 1 (high), 2 (rising) and 4 (falling). Is there vowel reduction in some tones or are those audios in this Pinyin chart bad?

**Tags:** pronunciation, tones
> **Comments:**
> **username_1**: I don't think so, because I never feel that way in Mandarin. Wha you said possible exist for third tone because sometimes 3rd tone is much longer than others, making middle part of a diphthong or triphthong much clearer  
> **username_1**: Most native speakers don't have the middle /o/ at all. But for a test, it might become a score point  
> **username_0**: Your first sentence in the first message is somewhat ambiguous and I'm not sure what you meant. You don't think that there is an extra /o/ sound in syllables with the ending -iu OR you do think that the extra sound exists, but that it does not disappears in tones 1, 2 and 4?  
> **username_1**: My Tone never changes my vowel.  
> **username_0**: Understood. And how do you pronounce Pinyin syllable "liu"? [liu] or [liou] ?  
> **username_1**: [liəu] or [liu]  
> **username_0**: Why do you pronounce it in 2 different ways?  
> **username_2**: Related question: [Why is it written LIU in Pinyin, when there's clearly an O sound?](https://chinese.stackexchange.com/questions/993) See iopq' answer, which suggests that there can be a difference in the pronunciation of the vowel between different tones.  
> **username_1**: Free-variant Allophone  

---

## 3 answers

### Answer by username_0 on 2019-09-17. Score: 5 | Accepted answer

First, it is important to distinguish between the phonemic pronunciation and the phonetic pronunciation. The first represents how native speakers interpret sounds, the latter interpret how the sounds are effectively performed.

The Pinyin final -iu is phonemically pronounced /jəu/, not /iou/ (reference: <https://en.m.wikipedia.org/wiki/Standard_Chinese_phonology#Allophones>). When combined with the Pinyin initial l-, that Pinyin final becomes the Pinyin syllable liu, phonemically pronounced /liəu/.

Anyway, much more important to a language learner is the phonetic pronunciation. The phonetic pronunciations of -iu may be [jəu], [jou] or even [jo̝u] (vowel O raises due to assimilation to the adjacent high sounds /j/ and /u/), which sounds similar to /ju/. The latter is the pronunciation in the audio recordings of the Pinyin syllable "liu" in the provided Pinyin table. The same also occurs in the audio recordings of the other Pinyin syllables with the final -iu.

Regarding the 3rd tone pronunciation of a Pinyin syllable with the final "-iu", when pronounced in isolation, it falls ([jo]) and then rises ([u]); in this way, this tone has an effect of separation and therefore tends to block the vowel assimilation that I mentioned before. That's why the [o] sound is heard in this tone and barely heard in the other tones in the audio recordings of the provided Pinyin table.

> **Comments:**
> **username_1**: "jou" isn't even an valid syllable in PinYin. What are referring? The 韵母 iou?  
> **username_1**: Also notice in normal continuous speech,  3rd tone is simply low and short as other tones, it doesn't usually have a rising part. So normally, the vowel doesn't change with tones at all.  
> **username_0**: I had meant the Pinyin final "-iu". I have fixed it. Thanks for pointing it out.  

---

### Answer by username_3 on 2019-09-17. Score: -1

I don't think there is a universal rule, but rather you just have to remember it as exceptions. Even for third tone "Liu3", it could be either /liu/ (溜, as in 你中文说得很溜) or /lio/ (六).


---

### Answer by username_4 on 2019-09-15. Score: -1

in Chinese Pinyin, o is prounounced as wooo,so ou can never occur, because wooou is difficult to prounounce in Chinese Pinyin. Only iu is allowed.

For the case ao, actually is au, but au in handwriting is apt to be confused with an, the latter occurs very frequently in Pinyin. To be distinct to an, the pronounce au is taken over by ao.

> **Comments:**
> **username_0**: "pronounced as wooo" = pronounced as English woo? If that's what you meant, that would sound /wu/ in IPA. Pinyin letter "o" does not have that sound in general; for instance, Pinyin syllables "ao" and "dong" are pronounced /ao/ and /doŋ/ (or /dʊŋ/).  
> **username_1**: Nobody knows what kind of sound you're talking about by just using Latin letters without any symbol system mentioned. And it's Pinyin or PinYin, not Pinying.  
> **username_2**: @AlanEvangelista: I'm guessing that cauckf is talking about the pronunciation of -o by itself as a final in the syllables *bo, po, mo, fo.*  

---

