Me, mine, you, yours

We've covered "you" (sinä) and "I" (minä) before, and noted the fact that when they're the subject, you usually don't include them in the sentence unless you're emphasising the fact that it's you or me you're talking about:

olen - I am
olet - you are
minä olen - it's me, I am
sinä olet - it's you, you are

Now, just as nouns can be altered using cases to indicate that something is "in the house" using the inessive (talossa), or you are going into the house using the illative (taloon), or something belongs to the house using the genative (talon), sinä and minä can be changed using cases too. However, some subtle differences come into play.

First here is the genative - if something is mine or yours, the ending changes to -un:

se on minun - it is mine
se on sinun - it is yours
minun auto on punäinen - my car is red
sinun kirja on kiinnostava - your book is interesting

A trickier case is the partative. We've already discussed the many meanings it can take. The main meaning is to indicate "some" or "part of" when it is used as part of the object of the sentence. In fact it is the most common case for words that are the object of the sentence. Strangely enough, it is used in the following sentences:

rakastan sinua - I love you
rakastatko minua - do you love me?

The accusative case is related, but rather than meaning "some of", it means "all of". If you want to tell someone to meet you, you want them to meet all of you (I know, you want them to love all of you too, but that's just an irregularity in the Finnish language), so you would say:

tapa minut - meet me
haluan sinut - I want you (all of you - to help out, for example)

With that last one you have to be careful, because if you said:

haluan sinua - I want you

it would actually mean "I want some of you" - which would carry the strong connotation of wanting to go to bed with the person. However, the following mistake:

rakastan sinut - I love all of you

althought technically incorrect, has a very poetic (and passionate) ring to it.