There are so many questions here, most of which are like 'How long is a piece of string?'. Here's somewhere to start:
Number of Words in the English Language . But don't regard it as the gospel truth; I've heard estimates of much more than 1 million 'words in the English language'. It rather depends on how you define a 'word' and what you mean by 'the English language'. Similar problems of definition haunt your other questions; what is 'an educated person'? My mother, who left school at 12, had a much bigger vocabulary than the PhD students whose doctoral theses she typed.
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