Bilingual reader for English books
A bilingual reader shows a book in two languages at once. Booklern is a bilingual reader built for learning English: the English original with a translation into Russian, Spanish, Brazilian Portuguese, Japanese, Chinese, Turkish or Arabic aligned sentence by sentence, in the browser, with audio, a dictionary and vocabulary tools, for 1,093 classics or any EPUB you upload.
What a bilingual reader does
The idea is old: printed parallel-text editions put the original on the left page and the translation on the right. A bilingual reader does the same on a screen, but with the two texts tied together at the level of the sentence, so a tap on any English sentence shows exactly its translation, never the wrong paragraph.
That alignment is the whole difference between reading with help and reading a translation. You stay in the English and use the other language as a check, not as the text you read.
Parallel text: two layouts
Booklern shows the translation either under each English sentence, which is the calmer layout for a phone, or in a second column beside the English, the classic parallel-text layout that suits a wide screen. A third setting hides the translation altogether, so you read English only and keep the dictionary and the audio. You switch between the three in the reader.
Hovering a word highlights the matching phrase in the translation. That is the part a printed parallel text can never do, and it is what makes idioms and word order visible without a grammar book.
Built for learners, not only for translation
A translation tool answers one question: what does this mean? A bilingual reader for learners has to answer the next ones too. Booklern reads the chapter aloud with the current sentence highlighted, gives every word a dictionary card with its pronunciation, saves words to a vocabulary list you can practise with generated stories, and scores your pronunciation when you read a passage into the microphone.
The bilingual library, and your own books
The library holds 1,093 public-domain classics with an estimated level each, browsable by level and genre. Several come with a published human translation aligned in advance; the rest are translated sentence by sentence as they are read. You can also upload an EPUB and read it the same way.
If you are choosing between parallel text and simplified books, the guide Parallel text versus graded readers sets out when each works.
