Verb conjugation of "leisten" in German

After testing the audio lab at the University of Bern, other universities such as the one in Zurich, ore the one in Geneva have shown interest. Of course, all this takes time. I will let you know.
My name is Wolfgang, and I am interested to build my Spanish vocabulary. Maybe we can practice together. How long have you learned Spanish? I have been learning for a few years with books.
Have you ever visited the U.S. before and if so, where have you been in the U.S.? I've been travelling in California, it was very amazing. We have traveled by car. Here are my corrections.