That´s what I'm talking about when i said be careful. In my example, when you look up in a dictionary in order to translate the statement "Lugar das Raizes" you wont find the correct term "root-loci", you'll find just the translation and that is not good enough. The best think you can do, it's improving your ability to take notes. When you're in the class, listen to the professor and take note about what you have understood in your own words in English. When you do that, you both realize the class as well as practice your English without translating.