I want to find some examples when article "the" changes meaning of an expression, can you help me and give some examples?
E.g.
I'm in the school.
Means I am in the building.
I'm in school.
Means that I'm a student.
In bed.
Refers to customary activities undertaken while someone is on the way to sleep.
In the bed.
Less likely to denote customary activity associated with sleeping and more likely to denote other activities.
It's not a duplicate of this question because it's not about the usage of a/an,zero or the article, it is about how an article can change meaning of a certain expression.