Hi Heli, I'm not a native English speaker but this happened to me before and luckily I've succeeded in controlling my speed as well as the structure of my conversations. It's not a problem If you speak slowly. Speaking slowly helps you control what you say better. Try to pronounce clearly while you speak and speak with the speed that you feel comfortable with. Do not try to eat the words. I know a lot of people who eat many syllables while they're speaking. That's not a good idea. To speak a foreign language fluently, you should try speaking alone (monologue) and speaking to native speaker (dialogue). Sometimes you should think of a topic and speak alone and record it. It will help you knowing what's wrong with your skills. Watch movies without subtitles, read articles and newspaper to get used to the language. That's what I've done. I hope it helps :(.