Svůj

I'm still working on my Czech.  Sometimes I feel like things are starting to come together and other times I feel like I'm going mad.

One of the peculiarities of Slavic languages is the use of "svůj".  It's a reflexive personal pronoun that basically means "one's own".  You use svůj in a sentence when the possessor is also the subject.  Clear as mud, right?

Řídím moje auto. = I drive my car.  

People will understand you but this is incorrect.

Řídím svoje auto.  = I drive my (own) car.  

This is the correct way to say this.  It's because the thing being possessed "car" is possessed by the subject "I" so you need to use svůj.

Using svůj can remove some of the ambiguity we sometimes have in English.  For example:

On vidí svého otce.  = He sees his father.  Meaning his own father.

On vidí jeho otce.    = He sees his father.  Meaning not his own father but the father of someone else.

So I concede that using svůj makes sense.  If only it was just svůj.  This is where Czech grammar gets fun.  First you need to know if the word 'being possessed' is masculine, feminine, or neuter because there are three genders in Czech.  Well actually 3,5 because if a word is masculine, you need to know if it is animate or inanimate.  You also need to know if you're talking about something in the singular or plural.

Then come the grammatical cases.  All seven of them in the singular and all seven of them in the plural.  So depending on how svůj fits in to the sentence grammatically it could actually be svůj, svá, svoje, své, svého, svoji, svojí, svému, svou, svém, svým, sví, svých, or svými.