Look up this word
careful

In a sentence
Nie si opatrný.
You are not being careful.
Musíš byť opatrný.
You must be careful.
Buď opatrný!
Be careful!
Buďte opatrný!
Be careful!
Examples from Tatoeba (CC BY 2.0 FR).
Source
Slovak National Corpus (SNK) ↗English gloss from the frequency publish path. Example sentences from Tatoeba (CC BY 2.0 FR).
Full attribution on References.