There is a group of masculine nouns that, except in the nominative case, receive an additional ending in all other cases. If the noun ends in '-e', the ending is 'n'; if it ends in a consonant, the ending is 'en'. Exceptions are 'der Bauer' and 'der Herr'.
Here are some subgroups
a) nouns with Latin origin: Dirigent, Kollege, Student, Präsident, Kandidat, Polizist
b) animal names ending in '-e': Löwe, Affe, Hase, Rabe, Falke
c) other nouns ending in '-e': Junge, Glaube, Funke, Gedanke
d) the only exception is 'Herz', a neuter noun 'dem Herzen, des Herzens'
Masculine nouns from weak declension
<p>There is a group of masculine nouns that, except in the nominative case, receive an additional ending in all other cases. If the noun ends in '-e', the ending is 'n'; if it ends in a consonant, the