This is the 8th most frequent Czech word.
ve
"Ve" is a Czech preposition meaning "in" or "into," used before words starting with certain consonants for euphony.
The word 've' means 'at' and is used with time expressions, here specifically indicating a time.
Budu na schůzce ve tři hodiny.
I will be at the meeting at three o'clock.
The word 've' here means 'in,' used before the word 'firmě' (a locative expression) to indicate a place of employment.
Pracuje ve firmě.
She works in a firm.
The word 've' means 'in' and is used here due to phonetic ease before a word starting with a consonant cluster, 'šk'. It indicates location.