DualBook 8 languages

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Make an English-Indonesian bilingual book

Each English paragraph with its Indonesian translation directly beneath it, in one EPUB. Read the English first; the Indonesian is there for the sentence that would otherwise stop you.

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

For an Indonesian reader learning English, the wall is usually the tense system. Indonesian says when something happened once and then leaves the verbs alone; English insists on marking it in every single verb, with a machinery of auxiliaries that has no counterpart to map onto. Rules do not fix that. Seeing the same sentence in both languages, again and again in real prose, does — because you watch what English repeats and Indonesian states once.

Your browser opens the EPUB, walks each paragraph and inserts the Indonesian beneath it as a sibling paragraph inside the original file. Only the chapter documents that receive a translation are rewritten, so cover, navigation, stylesheet and metadata survive as they were.

Stacked rather than facing columns — EPUB text reflows to the reader's screen and font size, and on a phone, which is where most of this reading happens, there is no room for columns anyway.

How it works

  1. Choose an English 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 relationships are mapped once, so kita/kami and the forms of address stay right across chapters.

  3. Indonesian 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 Indonesian. Read the English paragraph first, every time. The seconds of not understanding are the practice; skipping them means finishing a whole book having learned almost nothing.

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

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

Questions

Which side should I read first?

English first, every paragraph. With this pair the moment of not understanding is usually a tense resolving, which is worth more than any looked-up word.

Why is a parallel text good for this pair?

Because the hardest thing about English for an Indonesian reader is grammatical rather than lexical — the constant marking of time on verbs. Repeated exposure to the same sentence in both forms teaches that far faster than a tense table.

Will it open on a Kindle?

Yes. Kindle has accepted EPUB directly since 2022; 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