On time,in time .What are the differences?

[snowhite]

can someone sleep in bed?

 

[Aqua]

can someone sleep in bed?

Read between lines my explanation below and you will have the answer to your question.

 

[Mwanaukweli]

Michael Swan’s excellent Practical English Usage (Oxford University Press), provides a succinct answer to both of these questions:
"On time = at the planned time; neither late nor early:

Peter wants the meeting to start exactly on time.

In time = with enough time to spare; before the last moment:

He would have died if they hadn’t got him to the hospital in time." p. 450 Refer Prepositions - in time v on time - grammar - central - British Council - LearnEnglish

 

[Nsabhi]

hata mimi ndo naelewa hivyo. Maneno hayo!

Jibu nililitoa muda mrefu baada ya kuona watu hawatoi msaada:
ontime=exactly on the time arranged
intime=just before the time arranged(na siyo baada ya muda)

 

[pmwasyoke]

It is always good to arrive for appointments in time.

"In time" is a range starting well before the appointment, and ending "on time". In other words the exact point of on time is the last point of the line of in time.

 

[pmwasyoke]

can someone sleep in bed?

Sure. The bed here includes the sheets/blankets in addition to the basic structure.