Merge pull request #221133 from sally-baolian/patch-78

Update speech-synthesis-markup-pronunciation.md

Author: prmerger-automator[bot]

articles/cognitive-services/Speech-Service/speech-synthesis-markup-pronunciation.md

@@ -32,7 +32,7 @@ Usage of the `phoneme` element's attributes are described in the following table
 | Attribute | Description | Required or optional |
 | ---------- | ---------- | ---------- |
 | `alphabet` | The phonetic alphabet to use when you synthesize the pronunciation of the string in the `ph` attribute. The string that specifies the alphabet must be specified in lowercase letters. The following options are the possible alphabets that you can specify:<ul><li>`ipa` &ndash; See [SSML phonetic alphabets](speech-ssml-phonetic-sets.md)</li><li>`sapi` &ndash; See [SSML phonetic alphabets](speech-ssml-phonetic-sets.md)</li><li>`ups` &ndash; See [Universal Phone Set](https://documentation.help/Microsoft-Speech-Platform-SDK-11/17509a49-cae7-41f5-b61d-07beaae872ea.htm)</li></ul><br>The alphabet applies only to the `phoneme` in the element. | Optional |
-| `ph` | A string containing phones that specify the pronunciation of the word in the `phoneme` element. If the specified string contains unrecognized phones, text-to-speech rejects the entire SSML document and produces none of the speech output specified in the document. | Required |
+| `ph` | A string containing phones that specify the pronunciation of the word in the `phoneme` element. If the specified string contains unrecognized phones, text-to-speech rejects the entire SSML document and produces none of the speech output specified in the document.<br/><br/>For `ipa`, to stress one syllable by placing stress symbol before this syllable, you need to mark all syllables for the word. Or else, the syllable before this stress symbol will be stressed. For `sapi`, if you want to stress one syllable, you need to place the stress symbol after this syllable, whether or not all syllables of the word are marked.| Required |
 
 ### phoneme examples
 
@@ -41,7 +41,7 @@ The supported values for attributes of the `phoneme` element were [described pre
 ```xml
 <speak version="1.0" xmlns="http://www.w3.org/2001/10/synthesis" xml:lang="en-US">
     <voice name="en-US-JennyNeural">
-        <phoneme alphabet="ipa" ph="təˈmeɪtoʊ"> tomato </phoneme>
+        <phoneme alphabet="ipa" ph="tə.ˈmeɪ.toʊ"> tomato </phoneme>
     </voice>
 </speak>
 ```