Here is a great little passage from CS Lewis on thinking in Greek:
The great gain was that I very soon became able to understand a great deal without (even mentally) translating it; I was beginning to think in Greek. That is the real Rubicon to cross in learning any language. Those in whom the Greek word lives only while they are hunting for it in the lexicon, and who then substitute the English word for it, are not reading Greek at all; they are only solving a puzzle. The very formula, “Naus means a ship,” is wrong. Naus andship both mean a thing, they do not mean one another. Behind Naus, and behind navis or naca, we want to have a picture of a dark, slender mass with sail or oars, climbing the ridges, with no officious English word intruding.
You can read the full excerpt here: http://www.greekingout.com/2011/06/beginning-to-think-in-greek/