2.Minor declensions of the noun in Old Germanic language.
3.The evolution of the Old Germanic Noun in modern Germanic languages.
Proto- Germanic had six cases, three genders, three numbers, three moods [ indicative, subjunctive[PIE optative], imperative], and two voices [ active and passive [PIE middle]].
The system of nominal declensions was largely inherited from PIE. Six cases were preserved: vocative, nominative, accusative, dative, instrumental, genitive. The instrumental and vocative can be reconstructed only in the singular. The instrumental survives only in the West Germanic languages and the vocative only in Gothic. The locative case had merged into the dative case, and the ablative may have merged with either the genitive, dative or instrumental cases. However, sparse remnants of the earlier locative and ablative cases are visible in a few pronominal and adverbial forms, and in some instances the case forms of certain noun classes use the older locative ending for the dative
The older distinction between athematic and thematic stems had been lost, and generally nouns were divided into several declension classes based on the vowels or consonants before the case endings. Globally, there were vowel stems (a-, ō-, i- and u-stems) and consonant stems (n-, r- and z-stems and stems ending in other consonants). Usually, only nouns ending in consonants other than n, r or z are called consonant stems in the context of Proto-Germanic nouns. The neuter nouns of all classes differed from the masculines and feminines in their nominative and accusative endings