It might be added here that proper names also complicate morphological analysis: sandwich, Sequoia, sideburns, hooker. A common noun resulting from a proper noun is called an eponym. There are a few thousand eponyms in English. The creation of eponyms is one way that new free morphemes can enter the language. The presence of eponyms doesn't complicate morphological analysis because they, as well as the proper nouns that spawn them, are usually single morphemes. But eponyms do alter the morphological structure of the language, since many of them are multisyllabic rather than only one or two syllables long.