Which type of phrase is "unknown to him" in the following sentence?:
"Unknown to him, Beau had snuck into the trunk."
Is it an non-restrictive adverb phrase?
"Unknown" is an adjective, so it must be an adjective phrase. The comma marks the phrase as a supplementary adjunct, a loosely attached element set off by intonation and punctuation, presenting supplementary, non-integrated content. Supplements are by definition non-restrictive, though that's not a factor here.
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"Unknown" is an adjective, so it must be an adjective phrase. The comma marks the phrase as a supplementary adjunct, a loosely attached element set off by intonation and punctuation, presenting supplementary, non-integrated content.
Supplements are by definition non-restrictive, though that's not a factor here.
Incidentally, I would use "unbeknown" (rather than "unknown"), which so