This is the 820th most frequent Czech word.
dubnu
"Dubnu" is the locative or dative singular form of "duben," meaning "April" in Czech.
The word 'dubnu' in this sentence refers to the month of April used in the locative case to indicate 'in April'.
V dubnu kvetou stromy.
In April, trees bloom.
Here, 'dubnu' is used in the accusative case to indicate an action planned for the specific month 'April'.
Plánujeme dovolenou na dubnu.
We are planning a vacation for April.
In this sentence, 'dubnu' is used to indicate the time period within the month 'April' in the locative or instrumental context.