The words of a naturallanguage are concretely realized as word forms. For example, the English word write is realized as the word forms write, writes, wrote, written, and writing. The grammatical well-formedness ofnaturallanguage sentences depends on the choice of the wordforms. Words and word forms write writes wrote lohn has written a letter. writing In written English, word forms are separated by spaces. For practical purposes, this is sufficient for distinguishing the word forms in a text. Francis & Kucera 1982 define "a graphie word as a string of continuous alphanumeric characters with space on either side; may include hyphens and apostrophes, but no other punctuation marks." book - Words and morphemes Roland Hausser