DualBook 8 languages

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Make a Korean-Vietnamese bilingual book

Each Korean paragraph with its Vietnamese translation directly beneath it, in one EPUB. Read the Korean first; the Vietnamese is there when a sentence stops resolving.

The first 15 pages of text are sent to our server to be translated. The file itself stays on your device.

Korean is quick to start reading and slow to finish. Hangul takes a weekend; the grammar that hangs endings off the end of every verb takes years, and a dictionary is no help with an ending. That is exactly the gap a parallel text fills — you see what the ending did to the sentence, over and over, in real prose rather than in exercises.

For a Vietnamese reader there is a bonus the pair happens to provide. A large part of formal Korean vocabulary comes from the same Chinese roots as formal Vietnamese, so seeing the two stacked reveals correspondences that repeat: once you notice that a particular Korean syllable keeps matching a particular Vietnamese one, your vocabulary grows in blocks rather than one word at a time.

Your browser opens the EPUB, walks each paragraph and inserts the Vietnamese beneath it inside the original file, rewriting only the chapter documents that received a translation.

How it works

  1. Choose a Korean EPUB

    A DRM-free EPUB. The bilingual file is assembled in your browser, not on a server.

  2. The model reads the whole book

    The cast and their relative ages are mapped once, so the Vietnamese pronouns stay consistent throughout.

  3. Vietnamese is inserted under each paragraph

    Each translation is styled beneath its paragraph, easy to tell apart at a glance.

  4. Read it here, or on your phone

    A complete EPUB carrying the book's own fonts and stylesheets.

The trap, and the honest limits

Your eye will go to the Vietnamese. Read the Korean paragraph first, every time. The seconds of not understanding are the practice.

Fifteen pages get translations. The rest of the book stays in Korean inside the same file.

The text is sent to a server and discarded when the job ends. The file never leaves your device.

Stacked, not side-by-side — which is also what makes it usable on a phone, where most of this reading happens.

Questions

Which side should I read first?

Korean first, every paragraph. Reading the Vietnamese first means finishing a whole book having practised almost nothing.

Why is a parallel text good for this pair?

Because Korean's difficulty is in its verb endings and word order rather than in its vocabulary, and a dictionary cannot explain an ending. Seeing the finished sentence both ways, repeatedly, is what turns those endings into something you read rather than something you decode.

Will it open on a Kindle?

Yes. Kindle has accepted EPUB directly since 2022 and renders both Hangul and Vietnamese diacritics; email the file to your device or copy it across.

Do the cover and table of contents survive?

Yes. The browser rebuilds the archive entry by entry and only rewrites the chapter files that received a translation, so everything else passes through untouched.

The whole book, in parallel

The app builds the bilingual version of the entire book, with tap-to-look-up and your reading position synced across devices.

Open DualBook