@kazuki miyazaki I think the behavior you are seeing is expected since one of the requirement is to have English in from and to languages.
The
From
andTo
languages must include English and another supported language
If you are using Japanese to English this should work as expected but Japanese to Vietnamese will not work and will translate all the elements. Even though you are using en
as one of the two language the request to other to languages is treated as a separate request by the API and this will not apply dynamic dictionary in this case.
So, the below works as expected.(Ja->En)
Ja->Vi will translate the entire text and will not apply dynamic dictionary since en
is not part of to
and from
parameters.
If this answers your query, do click Accept Answer
and Yes
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