There are many words of French origin in English, such as art, collage, competition, force, machine, police, publicity, role, routine, table, and many others which have been and are being anglicized. They are now pronounced according to English rules of orthography, rather than French. Approximately 40% of English vocabulary is of French or Oïl language origin, most derived from, or transmitted by, the Anglo-Norman spoken by the upper classes in England for several hundred years after the Norman Conquest, before the language settled into what became Modern English.
William 1st of England:
Check out this list of words http://fr.wiktionary.org/wiki/Wiktionnaire:Liste_de_1750_mots_fran%C3%A7ais_les_plus_courants and try to guess those used in English.