Echetlaeus
Hero of Marathon
As any reasonable person would conclude, it's almost impossible to accurately list all the words in a particular language. However, if you compare the size of an English and a Greek dictionary, you'll see that the English dictionary (if comprehensive) is much larger. And I find it strange that you talk about the English language "borrowing" words from German and French, since English was derived from a fusion of West German dialects with Norman French superimposed on it after the Norman conquest. And there's nothing strange about English borrowing from Latin, since Latin was the lingua franca of the Middle Ages, as well as being the precursor of French. Some words are borrowed from Greek because they express an idea readily - Greek is quite useful for some things but ill adapted for others, whereas English is flexible enough for any task, and if it needs a word it doesn't have, it simply borrows from another language. English is better able than some other languages to digest foreign words, which is one of the things that makes it such a useful language. And the simplified grammer also helps. I'm glad we don't still have all the cases that we originally inherited from German, for example.
Aberdeen,
I like the approach that you have in the topic. You know I am not a linguist. I am just stating what I did in school. I do not think that the Greek dictionary fully reveals all the words that Greek language can create from its base. Some people talk about 6*10^6 entries, I am not sure though.