This is the 1389th most frequent Swedish word.
an
"An" in Swedish means "on" or "up to" when referring to proximity or limit.
Here, 'en' is the indefinite article for the common gender noun 'fågel' (bird), signifying one, unspecific bird.
Hon såg en fågel som flög högt på himlen.
She saw a bird flying high in the sky.
In this sentence, 'an' as individual word is not present, but part 'att vara' combined conveys continuity of presence or action.
De kommer att vara i mötet fram till klockan fyra.
They will be in the meeting until four o'clock.
In this case, 'anställning' as compound word means 'employment', demonstrating 'an' in embedded linguistic form.