The most important change found in Middle French is the complete disappearance of the noun declension system, which had been underway for centuries.
There was no longer a distinction between nominative and oblique forms of nouns, and plurals became indicated by simply an s. The transformations necessitated an increased reliance on word order in the sentence, which becomes more or less the syntax of Modern but with a continued reliance on the verb in the second position of a sentence, or "verb-second structure", until the 16th century.
Many words dealing with the military (alarme, cavalier, espion, infanterie, camp, canon, soldat) and artistic (especially architectural: arcade, architrave, balcon, corridor; also literary: sonnet) practices were borrowed from Italian.
[8] The influence of the Anglo-Norman language on English had left words of French and Norman origin in England.
The affirmation and glorification of French finds its greatest manifestation in La Défense et illustration de la langue française (The Defense and Illustration of the French Language) (1549) by the poet Joachim du Bellay, which maintained that French, like the Tuscan of Petrarch and Dante Alighieri, was a worthy language for literary expression and promulgated a program of linguistic production and purification, including the imitation of Latin genres.