Learn Finnish: Mihin opettaja menee? - Where is the teacher going?

In Finnish, location words change depending on movement. Missä means 'where', but only when someone or something is stationary. Because the verb menee involves movement towards a destination, you must use mihin, which specifically means 'where to'.

Could I use Minne instead of Mihin in this sentence?

Yes! Both mihin and minne mean 'where to' and are perfectly correct here. They are used interchangeably in everyday Finnish when asking where someone is going.

Why isn't the word on (is) used here for 'is going'?

Finnish doesn't have a separate 'is doing' continuous tense like English. The single verb menee translates to both 'goes' and 'is going'. Adding on to this sentence would be incorrect grammar.

How do we get menee from the dictionary word mennä (to go)?

To conjugate the verb mennä, you remove the -nä ending to get the stem men-. Because opettaja is a 'he/she' (third-person singular subject), we add -ee to the stem, resulting in menee.