From the Faraway Tree
They showed him the bed he was to sleep on.
And
Dick peered in at his window and saw the big owl asleep on a bed.
Considering this answer what context should I understand by the above sentence?
From the Faraway Tree
They showed him the bed he was to sleep on.
And
Dick peered in at his window and saw the big owl asleep on a bed.
Considering this answer what context should I understand by the above sentence?
Both "in" and "on" are possible.
When you are under the covers, you're "in bed". When you are shown to a bedroom where you will be spending the night, you're shown the bed you will "lie on" or "sleep on" or "sleep in".
I would choose "on" if I were shown to a cot, not a full bed.
The hotel room was small and since there were five of us, we had to sleep on cots.
So "on" could imply something like a cot.
Most Americans, I think, would also use "on" if complaining about the mattress or thinking of the bed in terms of its mattress. Some mattresses look as though they will deliver an unpleasant night's sleep.
I'd like to speak to the manager! This room was quite expensive, and yet the mattress was terribly uncomfortable. The springs were poking me and I couldn't get to sleep on that old bed!
When we think of the bed as a surface, we use on.
I put the luggage on your bed.
We slept on that bed last night.
Otherwise, we use in. In this sense, the bed is something that encloses us.
We slept in that bed last night.
Then there is the common usage in bed, which is just a fixed expression of the overall usage of in with bed.
You can also use at if you consider the bed to be a fixed point. We'll start the race at the bed and finish it at the table.
This all coincides with the normal distinction of in, on, and at, except that in bed does not usually refer to being inside the bed, as in inside the mattress, although that is not impossible.
I didn't sleep well last night? Why not? Didn't you sleep in that comfortable bed? Yeah, literally. Someone cut the mattress and stuffed me inside. Ah, so by in bed you mean inside the bed? Exactly.
See my answer that covers these three prepositions of place.