A fluent sentence can still be wrong. After using an AI translator, compare the result with the source for names, numbers, dates, units, negations, and technical terms. Check whether polite or informal language fits the audience and whether an idiom has been translated as meaning rather than word for word.
Read the translated text on its own to see whether it is understandable, then return to the original to catch missing or added claims. For a high-stakes document, use a qualified human reviewer who knows the subject and both languages.
Do not paste confidential material into a translation tool until you understand its privacy terms.
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