Questions & Answers about Ano, rozumím ti velmi dobře.
Because the verb rozumět (to understand) takes the dative case, not the accusative.
- ti = to you (dative, informal singular)
- tě / tebe = you (accusative or genitive, informal singular)
In Czech, you understand to someone grammatically:
- Rozumím ti. – I understand you (I understand to you).
- ❌ Rozumím tě. – ungrammatical
So with rozumět, always use dative: rozumím ti / vám, not tě / tebe / vás.
Yes, but the nuance is slightly different.
- Rozumím ti. – neutral, the normal everyday form.
- Rozumím tobě. – emphasizes you, often in a contrast: I understand *you, (not someone else / not something else).*
For example:
- Tobě rozumím, ale jemu ne. – I understand you, but not him.
In your sentence, Rozumím ti velmi dobře is the natural choice unless you need contrastive emphasis.