Being German and frequently talking to foreigners who study my difficult language I often hear them making the same mistake, by confounding the English and German "so".
Example from foreigners: "Ich habe viel Sport gemacht, so ich bin sehr müde heute." "Deutsch ist wichtig, so ich muss es lernen."
The German "so" is very different, so while Germans understand these sentences, grammatically they are not correct.
Instead of the English "so" we would use "also" --> "...also bin ich sehr müde heute / ...also muss ich es [Deutsch] lernen".
The German "so" is used like the English "as".
"Er ist so groß wie sein Vater."
I hope this helps those of you who learn German!