Two word forms for `have-actual-gender` noun

[jiedxu]

• If a concept can be assigned with a real word gender, there will be two word forms, a masculine one and a faminine one.
• There will be at least 18 spellings accociated with such concept.
• For example, Freundin is not supposed to be seen as an inflection of Freund, because there are also at least 8 inflection forms for Freundin.

In https://en.wikipedia.org/wiki/German_grammar#Gender:

Nouns denoting a person, such as die Frau ("woman") or der Mann ("man"), often agree with the natural gender of what is described. However there exist several notable counterexamples such as das Mädchen ("girl") and das Fräulein ("miss"), since the diminutive forms ending in -chen or -lein are grammatically neuter. Thus these are not illogical. However, gender and sex don't have to agree as in: das Weib (old, regional or anthropological: "woman"; a cognate of the English "wife"), der Mensch ("human", male or female), der Gast ("guest", male or female; the feminine Gästin is obsolete).

Furthermore, in German, the gender of nouns without natural gender is not comprehensively predictable. For example, the three common pieces of cutlery all have different genders: das Messer ("knife") is neuter, die Gabel ("fork") is feminine, and der Löffel ("spoon") is masculine.

To Do

• [ ] Two NounForm objects are required for concepts with natural gender.
• [ ] A new attribute, gender_equality.
• [x] Why there is grammar gender?