Questions & Answers about Tek sada shvaćam zašto je odgovor ispravan.
Here tek means only / just now / not until now.
So Tek sada shvaćam... gives the idea:
- Only now I understand...
- I’m only now realizing...
- Just now I understand...
It adds a sense that the understanding came late or only at this moment.
A useful comparison:
- Sada shvaćam = Now I understand
- Tek sada shvaćam = Only now do I understand
Yes, you can also say tek sad.
- sada is a bit more neutral or standard
- sad is very common in everyday speech
So these are both natural:
- Tek sada shvaćam zašto je odgovor ispravan.
- Tek sad shvaćam zašto je odgovor ispravan.
The meaning is basically the same.