Earlier today, Jeremy and I were discussing Quizlet flashcard study strategies. We are both making flashcard sets of words we see around town. That is one of the truly wonderful things about learning a foreign language in an immersion setting - so many of the words you are studying appear in your environment organically. Within a few days of moving here, for example, I learned a few month names and the days of the week without hardly trying, simply because I kept seeing them around the office. No artificial textbook scenario (or dictionary poring-over) needed.
Anyway, I asked Jeremy how he could be sure he was entering the nominative/base form of the word on the flashcard, without any conjugations or suffixes or cases. (What I mean by this is that we don't want to enter things like "to the store" when we mean to enter only "store." In English, it's three different words, but in Finnish, it could be one.) He said he usually double-checks with a dictionary to get at the root word without any appendages.
This all made me remember the time I lived in Russia for ten months, and spoke Russian quite well, before I realized that what I had thought was the nominative form of Jesus Christ, was in fact the accusative or genitive (and maybe even dative??) form of Jesus Christ - Иисус Христос vs. Иисуса Христа. I happened to see it in the nominative form on the cover of a Russian Liahona magazine and was like...oh my gosh...all this time...!
And to bring this post full-circle, that's the other thing that happens when you learn a language in an immersion setting. You often learn inductively instead of deductively - you make rules and learn words based on what you see and hear, rather than learning the rule first, explicitly. At church, most of what we do is talk about how we love Jesus, or have a testimony of Jesus, thereby putting it in a case. And for me, in Russia, this (quite naturally) led me to mistake Иисуса Христа for the nominative form.
Finnish class starts for me on Friday, and I can't wait to see what new words I'll start noticing around town...and entering correctly in my Quizlet set.