Translating With AI: The Prompt and the Pitfalls

The owner of a bed-and-breakfast in Vermont wants to translate her inn's description into Spanish for a booking site. She pastes her English text with an instruction: "Translate into Spanish." The result is readable and error-free, but problems remain that she won't see: "classic New England charm" translated word for word that sounds hollow, square feet that a Spanish reader can't picture, and perhaps a "sugarhouse" rendered by a vague equivalent. A traveler will roughly understand. They'll also hesitate to book.

AIs generally translate well, because they take context into account. But "into Spanish" isn't enough to frame the job. Everything you don't specify, it decides for you.

What to specify before translating

• The language variant. British or American English, Spanish from Spain or Latin America, Portuguese from Portugal or Brazil, French from France or Quebec. Vocabulary, spelling, and phrasing change.
• The reader and the use. A manual, a product sheet, an email to a supplier, and a restaurant menu aren't translated in the same register.
• The level of formality. Tu or vous in French, du or Sie in German, tú or usted in Spanish: the AI chooses based on the source text, which doesn't always match what's done in the target language for this type of document.
• What isn't translated. Names of products, places, dishes, brands, technical terms that your client knows in the original language.
• What gets adapted. Units, date formats, currencies, cultural references that don't exist elsewhere.

A prompt that frames the work

Translate the text below from English into Spanish (Spain).

Context: description of a bed-and-breakfast in Vermont, for a booking site. Readers: Spanish vacationers comparing several places to stay on their phones. Register: warm and direct, informal "tú", no brochure-style phrases.

Rules:
- Translate the meaning, not the words one by one. If an English expression has no natural equivalent, rephrase.
- Keep in English: "B&B", "sugarhouse" (add a short explanation of a few words in parentheses the first time).
- Convert square feet to square meters in parentheses, and leave the dollars as they are.
- Add no selling point that is absent from the text and remove no information.

At the end, add a "Points to check" list with the passages where you hesitated or where the meaning may change depending on the reader.

Text:
"""
[PASTE YOUR TEXT]
"""

The "Points to check" list is the most useful part. Without it, the AI delivers a translation that looks confident from the first line to the last, and you don't know where to look.

A glossary for texts that come back

If you translate regularly for the same activity, write a small glossary once and paste it every time: the term in the source language, the term to use, and possibly the term to avoid. A baker who sells "sourdough batards" and a pickleball club that talks about "the kitchen" don't have to re-explain their terms with every request. You can file this block with your reusable prompt templates, and it will serve you for every language.

The pitfalls to know

Omissions. In a long text, a sentence sometimes disappears, or a list gets shortened. Compare the number of paragraphs, bullets, and figures between the original and the translation.

False friends and idioms. A word that looks like one in your language can mean something else, and a figurative expression can be translated literally. If the text is full of humor or wordplay, expect an adaptation, and ask for it explicitly: "If a pun is untranslatable, offer an alternative that keeps the effect."

Proper names and numbers. Check names, addresses, prices, dates, and numbers by hand. These are the costliest errors, and what the AI changes least visibly.

Less common languages. The more widespread the target language, the more reliable the translation generally is. For a rarer language, or a dialect, expect more errors and have someone who speaks it review the result.

Formatting. If you're translating HTML or Markdown, say so: "Don't translate the tags or the links, only the visible text." Otherwise, you risk finding a translated web address.

Checking a translation in a language you can't read

If you don't speak the target language, you can't judge the result directly. A simple method is to open a fresh conversation, paste the translation, and ask for it to be translated back into English, without showing the original:

Translate this text into English as faithfully as possible, without embellishing or correcting it. Flag the ambiguous or awkward passages.

"""
[PASTE THE TRANSLATION]
"""

Then compare with your starting text. A meaning that shifts, a missing detail, or a tone that slips shows up quickly. The method has its limits: a subtle error can survive the round trip, and a text that back-translates well isn't necessarily natural. It mainly catches big gaps. To complement it, the article on verification gives a logic for checking according to the risk.

When to go to a professional

A contract, a manual that engages your liability, a medical document, an administrative file, or any text requiring a certified translation shouldn't be entrusted to an AI alone. For an official document, ask the receiving body what it requires, often a sworn translation. For the rest, AI can do the first draft, and a translator or native speaker does the review.

On the privacy side, what you paste into the tool leaves your computer. Reread what you're better off never putting in, especially for letters that contain client names or figures.

Your first try

Take a text of about ten lines that you'd have liked to translate, write the list of what must stay in the original language and the language variant you want, run the prompt, then do the back-translation. If you can show the result to someone who speaks the language, ask them to underline a sentence that sounds off. It will tell you what your prompt needs to specify next time.