Translation of twerp in German

There is a small misunderstanding about the homework. I can do them, but they will be too confusing? I am trying to find the article from where I took the sentences in order to ease the task for all students.
I do translate to Spanish, but I always inform the client about my problem, in order not to have any dispute. The corrections I receive after proof reading are mostly a confusion between the different time forms in Spanish.
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.