Translation of fertigstellen in German-English

I learned Russian during 8 years in highschool, but since I left school 6 years ago, I have forgotten most of it and did not have opportunity to speak or practice in any way. That's why I am on Vocabulix.
I've been working on and off on the dictionary during the entire week, and I'll spend some more hours on it this coming weekend. Sometimes he would get a bit mixed up and use formal Castilian sometimes instead of informal.
I have been studying Hungarian for one month. I also speak English, German and Latin. Hungarian would be my fourth language, and it gives me headache. I still can not say anything, not even one word.