Is it wrong to say:
"He occupies the bathroom, so I cannot come in"
I heard the phrase:
"The bathroom is occupied, so I cannot come in."
So I wondered if I also can say it the other way.
It's not wrong, but it is not a usual usage. Firstly, because the bathroom is being used for some significant time period, "he is occupying the bathroom" would be better. But this too sounds unnatural. Common-use expressions might be:
"The bathroom is occupied, so...."
"He is using the bathroom, so..."
"Fred is in the bathroom, so..."