@LuLi Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
. Please note that the Azure Translator service has Auto Language Detection which Automatically detect the language of the source text while using Text Translation or Document Translation.
. The language code ‘zh’ is a general code for Chinese, but it is not explicitly listed in the documentation because Azure Translator prefers more specific codes like ‘zh-Hans’ for Simplified Chinese and ‘zh-Hant’ for Traditional Chinese. The service still recognizes ‘zh’ as a valid input for Chinese, which is why your test worked. This isn’t a typo, but rather a preference for more specific language codes in the documentation.
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Hope this helps. If you have any follow-up questions, please let me know. I would be happy to help.
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