Novial was created as an international auxiliary language by Danish linguist Otto Jespersen, who introduced it to the world in 1928. Jespersen had previously been a co-author of Ido, which started to take form around 1907. Both languages base their vocabularies primarily on prominent Germanic and Romance languages, but differ grammatically in several important respects. Novial is more analytic in its grammar than Ido, and, in Jespersen's view, more natural.
In the Phonetic Novial spelling system (1928, 1930) the main differences between the Novial vocabulary and those of other systems come from the suppression of the letters c and z. The letter s plays an important part but tends to distort the visual appearance of some words (sientie = science, sesa = cease, sivil(i) = civil).
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The grammars of Novial and Ido differ substantially in the way that the various tenses, moods and voices of verbs are expressed. Both use a combination of auxiliary verbs and verb endings. However, Novial uses many more auxiliary verbs and few endings, while Ido uses only one auxiliary verb and a greater number of verb endings.
As with most international auxiliary languages, all verb forms in Ido and Novial are independent of person (1st, 2nd or 3rd persons) and number (singular or plural).
A PLANNED AUXILIARY LANGUAGE By Henry Jacob, 1947. A detailed comparative study of interlinguistics with full grammatical details of five systems of demonstrated usefulness, Esperanto, Ido, Occidental, Novial, and Latino sine flexione.