1. He called me while I was in bed.

2. he called me while I was sleeping.
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Does #1 mean #2? What is the meaning of 'in bed'?

1. He called me while I was in bed.

2. he called me while I was sleeping.
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Does #1 mean #2? What is the meaning of 'in bed'?

3. in bed: beneath the covers of a bed
(This is the definition of 'in bed.')
What is 'bed cover'? Is 'bed cover' different from 'blanket'? Do people sleep with bed covers or with blankets?

Being "in bed" and "sleeping" are not necessarily the same. One may sleep in a hammock, on a sofa, outdoors in the grass, in a chair, any number of places. And people do things in bed that are not sleeping, from reading to watching TV to sex, etc.

Bed covers refer to sheets and blankets, bedspreads, coverlets, etc. The things that cover the mattress.

In other words, to be IN bed is to be atop the mattress, covered with the bed covers, be it a sheet, a blanket, a coverlet, or a combination of them.

Yes, statement #1 "He called me while I was in bed" can mean the same as statement #2 "He called me while I was sleeping."

The phrase "in bed" generally refers to being physically present or lying inside a bed, while "sleeping" specifically means being in a state of rest where you are unconscious and unaware of your surroundings.

However, it is important to note that someone can be in bed without necessarily sleeping. They could be reading, watching TV, or simply relaxing. Therefore, while statement #2 implies that the person was asleep, statement #1 does not necessarily specify the person's level of consciousness; it only indicates their physical location inside a bed.