From 20 saved words to your own chapter: how it works in LingFit

The language app LingFit can generate a complete practice chapter from up to 20 saved words. To do this, words are first collected, then selected, and turned into a chapter at the push of a button. What matters most for the result is less the technology than the choice of words.

What it’s about

In many learning apps, a looked-up word ends up in a list that hardly anyone opens again. LingFit, developed by ThreeFlavors LLC, takes things a step further. The feature is called “Generate a chapter from words” in the app. The selected words become a chapter with the same exercise formats, audio files, and images as in the regular course. It appears in the “Yours” tab alongside self-created topic chapters.

Technically, it is an AI pack. Each pack costs one credit. According to the manufacturer, new accounts get a free credit; additional credits are bought in packages and do not expire.

Step 1: Collect words

The saved words list has its own tab in the navigation bar. Words get there in several ways:

• From the app: In lessons (with a long press), articles, grammar classes, and video subtitles (with a tap), a tooltip with a bookmark icon opens. A tap on it saves the word.
• Manually: Use the plus icon to enter any word with up to six translations.
• From other apps: Highlighted text from a browser, e-book, or chat can be sent to LingFit via “Share.” On Android, this works through the share menu and the text selection menu; on iOS, through a share extension.

The list shows the base form, so “go” instead of “goes.” It is stored on the device, works offline, and holds up to 2,000 words per learner.

Step 2: Select words

The central question is which 20 words belong in a chapter. A chapter works better when the words fit together. The AI builds sentences, dialogues, and fill-in-the-blank texts from them. Words from a shared context produce more natural exercises.

Proven selection criteria:

1. One topic per chapter: for example, all the words from a cooking video or from an email from a landlord.
2. Mixed parts of speech: Nouns, verbs, and adjectives combined produce complete sentences. Nouns alone lead to monotonous exercises.
3. Similar level: A chapter made up entirely of very rare words quickly becomes frustrating. Two or three difficult terms alongside more familiar ones are easier to process.
4. Less is allowed: A chapter does not have to have 20 words. Twelve well-chosen words are more useful than 20 random ones.
5. Use favorites: Important words can be marked with a star. The “Favourites” filter makes selection easier.

An example

A learner with German as a native language is learning Spanish and watches a video about a weekly market in the feed. She saves: mercado, puesto, fresco, maduro, pesar, el kilo, la oferta, regatear, barato, caro, probar, la cesta. From a reading text, she adds: el vendedor, la fruta de temporada, devolver.

These 15 words cover one situation: shopping at the market. The chapter can build dialogues between buyer and seller, fill-in-the-blank texts with prices, and image tasks about fruit. A chapter with “mercado,” “ordenador,” “tristeza,” and “aterrizar,” by contrast, would have hardly any shared context.

Step 3: Generate the chapter

After selection, generation starts via the button in the saved words list. The finished chapter appears in the “Yours” tab with its own emoji. The name and description can be changed later. If generation fails, according to the manufacturer, the credit is automatically refunded, and a notification informs you about it.

On request, the chapter can be made public after an automatic safety review. Other learners can then find, save, and like it. Private chapters remain visible only to the user.

Step 4: Practice and adjust

The chapter contains the exercise formats of the main course, from vocabulary cards to sentence building to speaking practice. Words that are answered incorrectly come back in the review round at the end of a lesson. If you still don’t retain a word, you can include it again in a later chapter.

If a translation is wrong or a sentence seems flawed in a lesson, the lesson can be reported directly. The report goes to the LingFit team.

Alternatives without a credit

Not every word list needs its own chapter. Saved words can also be practiced directly in the list as flashcards. This option is suitable for quick reviews; the chapter is for more thorough processing with listening, speaking, and sentence building. More information is available at lingfit.app.

The bottom line

The feature closes a gap that many learners know: looked-up words fall into oblivion. In LingFit, a collection becomes a practice chapter. The biggest influence on quality is your own selection. Thematically related words with mixed parts of speech produce the most useful chapters.