Translation of imprevisible

Work was performed only in June, July, August and September. In October and November, Erik has been waiting for Katja's visit and Sabine was on maternal leave after Christmas and New Year.
It is good if you have previously practiced only Spanish, which also shows that you are very good at other languages, and still can learn many things. I hope I'll learn it soon and practice.
I once had a lesson with a private teacher, but unfortunately she could not come regularly. She was always sick, then I have visited a school in Andalusia, which was worthless, since we talked only German.