This is the 20th most frequent Romanian word.
e
"Is" (third person singular of "to be").
In this sentence, 'e' is the third-person singular present tense form of the verb 'a fi', which means 'to be' in English.
El e fericit astăzi.
He is happy today.
In this case, 'e' functions as the third-person singular form of 'a fi', asking about the location of an object.
Unde e cartea mea?
Where is my book?
Here, 'e' is used impersonally to express that something is necessary, translating to 'it is' in English, emphasizing the indefinite subject.