Add more German vocabularies (#90)

README.md

@@ -55,6 +55,7 @@ Wilhelm Vocabulary
     * [German](#german)
       * [Pronoun](#pronoun)
       * [Noun](#noun)
+      * [Verb](#verb)
     * [Ancient Greek](#ancient-greek)
       * [Diacritic Mark Convention](#diacritic-mark-convention)
       * [Pronoun](#pronoun-1)
@@ -68,7 +69,11 @@ Wilhelm Vocabulary
 <!-- TOC -->
 
 __wilhelm-vocabulary__ is the data sources used for the flashcard contents on [wilhelmlang.com]. Specifically it's a
-datasource manually made from the accumulation of the daily language studies of [myself](https://github.com/Qubitpi).
+datasource manually made from the accumulation of the daily language studies of [myself](https://github.com/Qubitpi):
+
+- [German](./german.yaml)
+- [Latin](./latin.yaml)
+- [Ancient Greek](./ancient-greek.yaml)
 
 The data is available on 🤗 [Hugging Face Datasets][Hugging Face dataset URL]
 
@@ -416,6 +421,69 @@ For example:
 >     - [accusative, ████████, ██████]
 > ```
 
+#### Verb
+
+The conjugation is the inflection paradigm for a German verb. Those with `conjugation` field denotes a __verb__; its
+definition also begins with an _indefinite form_, i.e. "to ..."
+
+The reason for choosing [verbformen.com] is because of its comprehensive inflection info of German vocabulary provided.
+
+There are __3__ persons, __2__ numbers, and __4__ moods (indicative, conditional, imperative and subjunctive) to
+consider in conjugation. There are __6__ tenses in German: the present and past are conjugated, and there are four
+compound tenses. There are two categories of verbs in German:
+[weak and strong](https://en.wikipedia.org/wiki/Germanic_strong_verb)[^1]. In addition,
+[strong verbs are grouped into 7 "classes"](https://en.wikipedia.org/wiki/Germanic_strong_verb#Strong_verb_classes)
+
+[^1]: https://en.wikipedia.org/wiki/German_verbs#Conjugation
+
+The conjugation table of German verb on Wiktionary is hard to interpret for German beginner.
+[Netzverb Dictionary](https://www.verbformen.com/) is the best German dictionary _targeting the vocabulary inflections_.
+[Search for "aufwachsen"](https://www.verbformen.com/?w=aufwachsen) and we will see much more intuitive conjugation
+tables listed.
+
+This pretty much serves our needs, but what makes Netzverb unpenetrable by other alternatives is that _every_ verb comes
+with
+
+1. [A printable version that looks much better than the browser's Control+P export](https://www.verbformen.com/conjugation/aufwachsen.pdf)
+
+   - There is also a "Sentences with German verb aufwachsen" section with a
+     [link](https://www.verbformen.com/conjugation/examples/aufwachsen.htm) that offer a fruitful number of conjugated
+     examples getting us familiar with the inflections of the verb
+
+2. [An on-the-fly generated flashcard sheet](https://www.verbformen.com/conjugation/worksheets-exercises/lernkarten/aufwachsen.pdf)
+   which allows us to make a better usage of our random free time
+3. [A YouTube video that offers audios of almost every conjugated form](https://www.youtube.com/watch?v=LCtUrSn030A),
+   which helps with pronunciations a lot
+
+The entry for a German verb, hence, has an extra `verbformen` field that includes the links to the 3 pieces of
+information above
+
+```yaml
+- term:
+  definition:
+  audio:
+  verbformen:
+    video: 
+    conjugation:
+    flashcards:
+```
+
+For example:
+
+```yaml
+- term: aufwachsen
+  definition: to grow up
+  audio: https://upload.wikimedia.org/wikipedia/commons/f/f0/De-aufwachsen.ogg
+  verbformen:
+    video: https://youtu.be/LCtUrSn030A
+    conjugation: https://www.verbformen.com/conjugation/aufwachsen.pdf
+    flashcards: https://www.verbformen.com/conjugation/worksheets-exercises/lernkarten/aufwachsen.pdf
+```
+
+> [!IMPORTANT]
+> 
+> Note that some verbformen verbs do not have videos in which case the `video` field does not exist
+
 ### [Ancient Greek](./ancient-greek.yaml)
 
 Unless otherwise mentioned, we are always talking about _Attic_ Greek.

german.yaml

@@ -3553,6 +3553,7 @@ vocabulary:
       - to attach
   - term: das Wort
     definition: the word
+    audio: https://upload.wikimedia.org/wikipedia/commons/7/7c/De-Wort2.ogg
     declension:
       - ["",         singular,        plural           ]
       - [nominative, Wort,            "Wörter, Worte"  ]
@@ -3959,6 +3960,18 @@ vocabulary:
       - [genitive,   Examens,  "Examen, Examina"]
       - [dative,     Examen,   "Examen, Examina"]
       - [accusative, Examen,   "Examen, Examina"]
+  - term: benutzen
+    definition: to use
+    audio: https://upload.wikimedia.org/wikipedia/commons/d/da/De-benutzen2.ogg
+  - term: die Übung
+    definition: the practice
+    audio: https://upload.wikimedia.org/wikipedia/commons/7/7f/De-%C3%9Cbung.ogg
+    declension:
+      - ["",         singular, plural ]
+      - [nominative, Übung,    Übungen]
+      - [genitive,   Übung,    Übungen]
+      - [dative,     Übung,    Übungen]
+      - [accusative, Übung,    Übungen]
 
 
 
@@ -4137,6 +4150,11 @@ vocabulary:
       - [ accusative, Viertel,  Viertel ]
   - term: aufwachsen
     definition: to grow up
+    audio: https://upload.wikimedia.org/wikipedia/commons/f/f0/De-aufwachsen.ogg
+    verbformen:
+      video: https://youtu.be/LCtUrSn030A
+      conjugation: https://www.verbformen.com/conjugation/aufwachsen.pdf
+      flashcards: https://www.verbformen.com/conjugation/worksheets-exercises/lernkarten/aufwachsen.pdf
   - term: der Erwachsener
     definition: (male) the adult
   - term: die Erwachsene
@@ -4789,6 +4807,7 @@ vocabulary:
     definition:
       - (adj.) only
       - (adj.) unique
+    audio: https://upload.wikimedia.org/wikipedia/commons/c/c5/De-einzig.ogg
   - term: gewonnen
     definition:
       - (adj.) gained
@@ -5655,6 +5674,11 @@ vocabulary:
       - to supply
       - to provide
       - to research
+    audio: https://upload.wikimedia.org/wikipedia/commons/e/ee/De-liefern.ogg
+    verbformen:
+      video: https://youtu.be/-5h4JgcuSc4
+      conjugation: https://www.verbformen.com/conjugation/liefern.pdf
+      flashcards: https://www.verbformen.com/conjugation/worksheets-exercises/lernkarten/liefern.pdf
   - term: der Begriff
     definition:
       - the term
@@ -5662,6 +5686,13 @@ vocabulary:
       - the idea
       - the conception
       - the perception
+    audio: https://upload.wikimedia.org/wikipedia/commons/c/c2/De-Begriff.ogg
+    declension:
+      - ["",         singular,              plural   ]
+      - [nominative, Begriff,               Begriffe ]
+      - [genitive,   "Begriffes, Begriffs", Begriffe ]
+      - [dative,     Begriff,               Begriffen]
+      - [accusative, Begriff,               Begriffe ]
   - term: zuletzt
     definition: (adv.) finally
   - term: mithin
@@ -5915,3 +5946,15 @@ vocabulary:
       - (conj.) so that
       - (conj.) in order that
     audio: https://upload.wikimedia.org/wikipedia/commons/f/f0/De-damit3.ogg
+  - term: zweitens
+    definition: (adv.) secondly
+    audio: https://upload.wikimedia.org/wikipedia/commons/9/9a/De-zweitens.ogg
+  - term: abtrennen
+    definition:
+      - to cut off
+      - to separate
+    audio: https://upload.wikimedia.org/wikipedia/commons/d/d9/De-abtrennen.ogg
+    verbformen:
+      video: https://youtu.be/eC5wJ5kA6js
+      conjugation: https://www.verbformen.com/conjugation/abtrennen.pdf
+      flashcards: https://www.verbformen.com/conjugation/worksheets-exercises/lernkarten/abtrennen.pdf