我很新学习Microsoft Azure的文本到语音（TTS）服务。我成功地能够通过使用Azure的TTS服务将给定文本转换为音频文件。当我在SSMLXML文档中有一个voice元素时，它工作正常。使用SSML的例子是：

<speak version="1.0" xml:lang="en-US">
  <voice xml:lang="en-US" xml:gender="Male" name="en-US-Jessa24kRUS"> 
       Hello, this is my sample text to convert into audio? 
  </voice>
</speak>

但是，当我有多个语音标签（基于性别）时，它会导致错误。其中SSML为：

<speak version="1.0" xml:lang="en-US">
  <voice xml:lang="en-US" xml:gender="Male" name="en-US-Guy24kRUS"> What’s your name? </voice>
  <voice xml:lang="en-US" xml:gender="Female" name="en-US-Jessa24kRUS"> My name is Cindy Smith. Do you know John Silver?</voice>
  <voice xml:lang="en-US" xml:gender="Male" name="en-US-Guy24kRUS"> John and I are old friends. </voice>
  <voice xml:lang="en-US" xml:gender="Female" name="en-US-Jessa24kRUS"> John just joined our company as a salesperson. </voice>
  <voice xml:lang="en-US" xml:gender="Male" name="en-US-Guy24kRUS"> That’s good news. John has been a salesperson for chemical products for many years. </voice>
  <voice xml:lang="en-US" xml:gender="Female" name="en-US-Jessa24kRUS"> I head he really likes his new job.</voice>
</speak>

错误是：
响应状态代码不表示成功：400（SSML必须包含最多5个语音元素。实际数字6）。

**如果有人解释为什么限制我使用5个voice tags，而documentation中没有提到限制，这对我来说将是一个很大的帮助。