Have you already think that your level is so high and others times that you are very weak? I'm usually very confident to speak English, but sometimes I forget some simple words and I have difficult to explain my ideas. Sometimes, I think that I can understand almost all things that I listen to in a movie, but other times it looks like how I don’t know anything in the language. In short: sometimes I believe that I made a big progress improving my English, but other times it looks like I still have a big road forward. Has it already happened with you studying a foreign language?