Difference between zbyt and za

I know that 'za' has a few different meanings, but where it means 'too', what difference is there between za and zbyt?

I used to think that zbyt was used in a subjective statement, expressing one's personal opinion; jesteś zbyt stary - you're too old, and za is used in conjunction with another clause making it more matter of fact; jesteś za stary by wstąpić do wojska - you're too old to join the army. Then I was told that zbyt it used in simple, direct statements; zima w Polsce jest zbyt zimna - winter in Poland is too cold, and za is used in indirect statements; zima w Polsce może być zbyt zimna - winter in Poland can be too cold.

Are either of these right? Or are the words interchangeable? What are the rules exactly?

It's whatever sounds good, as is often the case in language. For example, explain to me why it's na Litwie rather than w Litwie, or Na £otwie rather than w £otwie! It just is and that's it!! Most countries follow w (in) but there are exceptions (Hungary)

The same as zbyt mało and za mało. Zbyt is gramatically sound but the great majority of native speakers, I reckon, would go with za mało. It rolls off the tongue better.

Certain words go better together and that's why we have collocations and instinctive speech production.

Thanks Seanus. I didn't know that about 'na Litwie'.

For example, ask yourself which sounds better:

Za bardzo zadowolony - too glad
Zbyt bardzo zadowolony - too glad

I'd say za bardzo sounds better as the sound combination (vowel plus consonant) rolls together better and is shorter. Like we wtorek rather than w wtorek.

That's true, but we still say w Polsce, w Londynie and w Szczebrzeszynie. ;)

Btw, do w świecie and na świecie mean the same thing?

Lew jest królem w świecie zwierząt. (domain)
The Lion is king in the animal world.

Niemieckie autostrady są najlepsze na świecie. (globe)
German highway infrastructure is the best in the world.

If we swap these two they sound strange.

That's because those sounds go together well, Czwartek. They don't require a bending of the tongue ;) ;)

I have tried saying "zbyt" instead of "za", but I don't feel comfortable with it. When trying to say something is toooooo big, tooooo bright, TOOOOOOO messed up or whatever, "za" seems easier to intonate in a way that makes it sound toooooo this or toooo that. "Zbyt" sounds like such a little word whereas "za" can sound quite big. That is to my ears anyway.

Looking at it from the other side, zbyt rolls well with the negative as a general comment to say 'not really'. Lubisz X? Hmm...nie zbyt. Nie zbyt + adjective can often be like not so, rather than 'not too'.

niezbyt is one word meaning not so much, not really etc

niezbyt is roughly the same as 'nie za..'

Zna pan niemiecki?
Niezbyt dobrze/ Nie za dobrze. (Za dobrze means too good)

Do you know German?
Not really good.

Aha, thanks for that, gumishu. I had always assumed that they were 2 separate words. I occasionally do that and the Pole is surprised that I'm breaking the word up.

Hmm...when I start doing that in English I'll begin to worry ;)