This is the 67th most frequent Norwegian word.
gjennom
"Through"
Here, 'gjennom' implies duration over a period of time, emphasizing the continuity of work throughout the night.
Vi jobber gjennom natten for å bli ferdige.
We work through the night to finish.
In this context, 'gjennom' is part of the noun 'gjennomgang', which means a review or walkthrough, showing its use in a compound form implying thorough examination.
Hun fikk en gjennomgang av dokumentet.
She received a review of the document.
In this sentence, 'gjennom' is used as a preposition to indicate movement across or within a place, specifically describing passage through a forest.