Answer: It's been covered extensively on Quora. In brief, it's mainly because England was conquered in 1066 by the Norman French, who made their language the law of the land for about 250 years. French is largely derived from Latin. read more
3) A major amount of vocabulary - particularly in scientific, medical and cultural fields - dating from the Renaissance, when Latin and Greek were the languages of intellectual discourse, so many new terms were coined from Latin roots. read more
Many words do; new words on technical, scientific, philosophical topics have been created from Greek and Latin for many centuries, often mixing the two languages. This habit still occurs. Also, you have many words that were imported from French in the centuries after Norman conquest (because large parts of France and England were ruled commonly, and there was a lot of cultural exchange). read more