Collocations for occupied - adj.

be

densely
the most densely occupied areas of the country

entirely
The sofa was entirely occupied by two large cats.

permanently
illegally

be
become
keep sb
We need something to keep the children occupied.

fully (esp. BrE)
happily

in
You will be mainly occupied in checking sales records.

with
She was happily occupied with reading.

Occupied is used with these nouns:
country, territory, zone