Slow down your sending, and if the other guy is still too fast, send "QRS PSE, ENGLISH NOT MY LANGUAGE". Then maybe echo back something that you partially received, and let him fill it in. If he doesn't slow down for you, say 73 and move on to someone who will. While different people have different preferences, I know I'm not alone in preferring a slow "rag chew" conversation on random topics over a fast "rubber stamp" QSO. You will find plenty of people to talk to if you slow down and/or ask them to slow down. And I believe you will be admired much more for attempting to communicate in Morse code using a language that is not your native language. The W1AW practice sessions have English text at various speeds. I don't know how well you can receive them over the air at your location, but they're available online at http://www.arrl.org/code-practice-files .