Here's a breakdown:
* 1066-1200: French was the language of the court, government, and aristocracy. English was spoken by the common people.
* 1200-1400: English started to regain ground. The rise of a new English middle class and a growing sense of national identity contributed to this.
* 1400-1500: English became the dominant language of the country. French still had some influence, particularly in legal and administrative contexts.
Therefore, it's difficult to say exactly "how many years" after the conquest French was spoken in England, as it was a gradual process of language shift and coexistence. French remained a significant language in England for several centuries after the conquest.