Translation of falter in German

I started to speak Spanish because i had i boyfriend from Mexico. Especially I've never learned Spanish . I only listened and repeated what he spoke. Now i speak Spanish well but i need to learn grammar rules.
I wish you a good trip, when you come to Germany in June! How do you long stay in Berlin? Please help me with my English, in return I will help you with your German. Wish you a nice day!
I actually wrote you earlier, but everything got erased when I accidentally closed my browser window. Anyway, you want to know about the Germany. I can send you some information and send you some links.