Hello Torsten, thank you for you advice, I listen to mp3 files while I drive to my work some of them are easy and I can understand almost everything. But at home I watch CNN or TV series like Friends or Two and Half Men but I can not understand almost nothing. They talk fast and use many slangs. I feel frustrated. Thanks again.
Yes this can be a problem for some. The programs you mentioned may not have this problem, but I have found many American (and some English) films programmes are hard to understand because of the accent, and not just the speed. But I would advise that you keep up with it. I think you will find that you will learn a lot of useful phrases that you would not normally learn.
Can you watch these programmes with English subtitles? I have found this has helped many people who are learning English. maybe this would help you understand better and you can see the phrases and maybe look them up on the internet (or on this forum!)