Translation of hippo in German

I want to improve my level of English. Have you ever been in the U.S. and in which states have you been? I've been in England, Scotland and Ireland, but unfortunately, I have never been to America.
I think that it is easy to find new students, as many of them have already visited schools in Switzerland or Germany, but most of them have been to Berlin. Spanish learning is less common these days.
I apologize that I have not written for such a long time! Please call me on my new phone number, that would be great! How is your son feeling, has he been recovering? I am sure that he will be fine.