internal WordContentVertex WordContentVertexFor(WordElementBuilder partOfSpeech) => WordContents.Single(vertex => vertex.Model == partOfSpeech);
/// <summary>Return the vertex representing the word contents that correspond to <paramref name="partOfSpeech"/></summary> internal WordContentVertex WordContentsCorrespondingTo(WordPartOfSpeechVertex partOfSpeech) => WordContents.Single(vertex => vertex.Model == partOfSpeech.Model);