Every flashcard in flangu is the same basic object: two sides and a set of content attached to those sides. This article describes each piece of that content and what it does.
The two sides
A flashcard has a front and a back.
The front holds the word or phrase you want to learn. The back holds its translation. Each side has its own language assigned, shown as a flag in the top corner of the card panel.
The two panels share one screen, and that screen does not scroll. Longer content scrolls inside its own panel instead.
Note
Text on a card follows your device's text size setting up to 1.3 times the standard size. Above that, card text stays at 1.3 times, so both sides still fit on the screen together. This limit applies only to the card panels.
The language assignment matters for more than display. It determines which voice is used for audio playback, and it is part of the key the app uses to look up and store linguistic metadata.
Metadata
After a card is created, flangu attaches a set of linguistic metadata to it. This metadata lives on both sides and is organized into four named sections. You access each section by tapping its icon in the icon row at the bottom of each card panel.
Synonyms and Alternatives
The front side shows 
Synonyms: words in the same language as the front that share a similar meaning.
The back side shows 
Alternatives: other valid translations of the front word that were not used as the primary back. These are not the same as synonyms. Synonyms are words with the same meaning in the same language; alternatives are different but equally correct translations.
For example, if the front is "plant," synonyms might include "flora." If the back is "la planta" (Spanish), alternatives might include "la fábrica" and "la central."
Each alternative shows a short note in the front's language that says which meaning it has: "la fábrica" is marked "factory" and "la central" is marked "power station." See Linguistic metadata.
Definition
Each side can have its own 
Definition: a short explanation of what the word means in that side's language. The front definition explains the word in the source language. The back definition explains it in the target language.
Not every card has a definition. Numerals, full sentences, and questions do not receive one.
Example sentences
Each side can have multiple 
Example sentences showing the word used in context.
The examples are displayed in a carousel: swipe left or right to move between them. Both sides of the card share a synchronized position in the carousel, so if you are on example 2 on the front, the back also shows example 2.
Note
Free users see one example sentence per side. Additional examples require flangu Pro.
Each example sentence has its own audio. Tap the sentence to hear it spoken.
Pronunciation
The Pronunciation section shows a written representation of how the word sounds. Most languages use an IPA transcription. Some use a format learners of that language already know: pinyin for Chinese, a hiragana reading with romaji for Japanese, and the word with its stress marked for Russian. See Pronunciation for the full list.
This is separate from audio. Pronunciation is text. Audio is synthesized speech, described in the next section.
Audio
Every card panel has a 
speaker icon. Tapping it plays a synthesized spoken pronunciation of that side's text. This is text-to-speech (TTS) audio, generated on demand the first time you tap the icon and cached for instant playback on every subsequent tap.
Audio is generated separately for each side. Each individual example sentence also has its own audio: tap the sentence to hear it spoken.
Vocabulary image
Eligible cards show an 
image icon on the front panel. Tapping it generates an illustrative vocabulary image for the concept the word represents.
Not every card is eligible. Images are generated for concrete, visualizable concepts: primarily nouns, proper nouns, verbs, and adjectives. Abstract parts of speech, full sentences, and questions are not eligible and will not show the image icon.
Note
Vocabulary images are a Pro feature.
Part of speech
Each card is assigned a part of speech label, shown in abbreviated form directly on the card panel below the word. For example: n. for noun, v. for verb, adj. for adjective.
| Abbreviation | Full label |
|---|---|
n. |
Noun / Proper noun |
v. |
Verb |
adj. |
Adjective |
adv. |
Adverb |
pron. |
Pronoun |
prep. |
Preposition |
conj. |
Conjunction |
det. |
Determiner |
num. |
Numeral |
intj. |
Interjection |
phr. |
Phrase |
idm. |
Idiom |
sent. |
Sentence |
ques. |
Question |
The part of speech is assigned automatically when the card is translated, or when metadata is generated for a manual card. It is not directly user-editable.
The part of speech affects what metadata a card receives and how many items each list holds. Sentences and questions get no definitions, synonyms, or examples. Nouns, proper nouns, verbs, and adjectives are eligible for a vocabulary image; other parts of speech are not. See Part-of-speech and length gating for the full rules.
Phrase and sentence cards
A card's front and back aren't limited to single words. Anything up to 500 characters can go in either side, so you can create cards for set expressions, idioms, full sentences, or questions the same way you'd create one for a single word.
Longer input is classified as one of four parts of speech: phr. (phrase), idm. (idiom), sent. (sentence), or ques. (question). That classification determines what metadata the card receives:
- Phrase and idiom cards receive a translation, synonyms, a definition, alternatives, example sentences, pronunciation, and TTS audio, the same as a single word.
- Sentence and question cards receive a translation, alternatives, pronunciation, and TTS audio. They do not receive synonyms, a definition, or example sentences.
- None of the four are eligible for a vocabulary image; only nouns, proper nouns, verbs, and adjectives are.
Scheduling is unaffected by length or part of speech. FSRS-6 treats a sentence card exactly like a single-word card — see The FSRS-6 algorithm.
The Personal Tutor also offers quick-action prompts tailored to phrases and idioms, such as origin and usage explanations.
Card state
Below the card content, flangu displays the card's current status badge: a colored label that shows where the card is in the learning schedule.
| Label | Color | What it means |
|---|---|---|
| New | Blue | The card has not been reviewed yet. |
| Learning | Red | The card is in an active learning phase. This covers both cards being learned for the first time and cards that were forgotten and are being relearned. |
| Due | Green | The card has been learned and is scheduled for review right now (or is overdue). |
| Upcoming | Gray | The card has been learned but is scheduled for review in the future. |
The state changes after each review based on how you rated the card. The full explanation of how states transition and what they mean for scheduling is covered in the Reviews section.