Now let's come to the Middle English. In 1066 William the Conqueror, the Duke of Normandy, which is part of modern France, invaded and conquered England. The new conquerors called the Normans brought with them a kind of French, which became the language of the Royal Court, and the ruling and business classes. For a period there was a kind of linguistic class division, where the lower classes spoke English and the upper classes spoke French. In the 14th century English became dominant in Britain again, but with many French words added. This language is called Middle English. It was the language of the great poet Chaucer. Middle English was still a Germanic language but it is different from Old English in many ways. Grammar and the sound system changed a good deal. People started to rely more on word order and structure words to express their meaning rather than the use of case system. "This can be called as a simplification but it is not exactly. Languages don't become simpler, they merely exchange one kind of complexity for another", Clark and Eschholz says. Middle English would still be difficult for native English speakers to understand today. Following up is the early Modern English. Towards the end of Middle English, English underwent a couple of sound changes. One change was the elimination of a vowel sound in certain unstressed positions at the end of the words. The change was important because it affected thousands of words and gave a different aspect to the whole language.