This is the 822nd most frequent Swedish word.
pojken
"The boy."
Here, 'pojken' is the subject of the sentence, indicating the person (a boy) performing the action of running.
Pojken springer snabbt.
The boy runs quickly.
In this sentence, 'pojken' is the object of the sentence, specifying the person being observed.
Jag tittar på pojken som leker i parken.
I am watching the boy who is playing in the park.
'Pojken' is used here in a relative clause to specify the person being referred to with a possessive relationship.