Living in a neighboring country I understand nothing of Finnish. Spanish, Italian, French — I can make some sense out of it without knowing the languages.
I must however add that I've witnessed, more than a handful of times, English speaking knowledge workers moving to Sweden who continue speaking English and only English for years and years.
It comes with a social price though. You will never quite understand all the social codes or become a part of the social fabric. At many parties and dinners I've seen the whole group having to switch to English because there's someone in the group who has lived here for five or ten years and still haven't gotten around even attempting to speak Swedish. Everyone will switch but but it will be a different night, without all the nuances we usually enjoy. In the end everyone loses.
If you plan to stay, do everything to learn the language. You will be happier person in your new country.
