Here's a link to an excellent document that you can use to build your English vocabulary.
Greek and Latin Roots Document
A few years back, the "Google Books Project" scanned essentially every book found in a sampling of major universities around the world. The project teamed up with Harvard Math to estimate the total number of words in the English language: about 1,000,000, and growing by about 8,500 words per year. Consider that when Shakespeare was writing his sonnets and plays and when Wycliffe was translating the Bible into English, there were only about 50,000 words in the English language!
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