This is the 4th most frequent Bulgarian word.
е
The Bulgarian word "е" means "is" in English.
The word 'е' is used as the third person singular present tense form of the verb 'съм' (to be), serving as a copula to link the subject 'Това' to the predicate 'книга'.
Това е книга.
This is a book.
Here, 'е' serves as a state-descriptive link between the subject 'Времето' and the compounded predicate 'студено', indicating its current condition.
Времето е студено.
The weather is cold.
In this sentence, 'е' functions to link the subject 'Тя' to the predicate adjective 'красива', describing a characteristic of the subject.