This is the 2717th most frequent Polish word.
domem
"Domem" is the instrumental singular form of "dom," meaning "house" or "home" in English.
In this sentence, 'domu' (a different case of 'domem') is used in the locative case to describe the location where the subject lives.
Mieszkam w domu z czerwonym dachem.
I live in the house with the red roof.
Here, 'domem' is used in the instrumental case to signify the means or object of the sharing.
Chcemy podzielić się naszym domem z nowymi sąsiadami.
We want to share our house with the new neighbors.
In this example, 'domem' is in the instrumental case to signify the place in relation to the action of walking.