"He felt himself lifted on to one of the sacking beds and immediately sank into a deep sleep."
I haven't understood the first section. Please help.

Question

Answer

Someone else lifted him and put him on the bed.

Answer

The first section is in passive voice, which means the action is being done to the subject of t,he verb.   The missing word is'being' - he felt himself being lifted (by others) on to the sacking bed.

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