My husband was sound asleep.
According to Merriam Webster, the word "sound" in "sound asleep" is an adverb. What part of speech, then, is "asleep"? ("Asleep" can only be an adjective or adverb, and not a verb?)
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Sign up to join this communityMy husband was sound asleep.
According to Merriam Webster, the word "sound" in "sound asleep" is an adverb. What part of speech, then, is "asleep"? ("Asleep" can only be an adjective or adverb, and not a verb?)
An adjective modifies (describes) a noun.
An adverb can modify an adjective to provide more detail:
Some adjectives can only be used predicatively (following a copula as in these examples). Asleep is one of those; afraid is another. [Source: UCL]
Some adjectives can only be used attributively (before the noun). Main is one such.
A comment has mentioned that afraid and asleep are preposition+noun phrases which were eventually reinterpreted. This may well be the case, and probably explains why they are only available predicatively. It doesn't necessarily assert that they are now adverbs rather than adjectives.
An adjective doesn't necessarily have to be followed by a noun.
see other examples of adjectives preceded by adverbs: "completely wrong", "always late", "never cold"
Note the following:
An adverb is a word that modifies a verb, adjective, another adverb, determiner, noun phrase, clause, or sentence.
Therefore an adverb can modify an adjective, e.g.
The baby is sound asleep --> Noun phrase/verb/adverb/adjective
EDIT (in response to a comment)
Definition of asleep in English: adjective& adverb
1 In or into a state of sleep:
[AS ADJECTIVE]: she had been asleep for over three hours
[AS ADVERB]: he soon fell asleep
You can see that, according to this dictionary, when 'asleep' is used in this way with the verb 'to be', it is considered an adjective.