Valmy is in bed, asleep.
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Can you paraphrase the sentence?
What is the function 'asleep' in the sentence?
1. Valmy is in bed, while he is asleep.
2. Valmy is in bed, and he is asleep.
Does the original sentence mean #1 or #2? Or other sentences?
The original sentence and #2 mean about the same thing.
"asleep" is an adjective in those sentences, modifying "Valmy" in the original sentence and modifying "he" in the paraphrase.
The sentence "Valmy is in bed, asleep." can be paraphrased as "Valmy is currently sleeping in bed."
In the sentence, the function of the word "asleep" is to describe Valmy's state or condition. It indicates that Valmy is in a state of sleep or is currently sleeping.