Latin is an inflected language, and as such its nouns, pronouns, and adjectives must be declined (their endings alter to show grammatical case). A set of declined forms of the same word pattern is called a declension. There are five declensions, which are numbered and grouped by ending and grammatical gender. For simple declension paradigms, visit the Wiktionary appendices: , , , , . Each noun follows one of the five declensions, but some irregular nouns have exceptions.