Clarifying grammar question
The question asks if "by trees" in "surrounded by trees" is an adverbial. In English, "by trees" is a prepositional phrase that complements the past participle "surrounded." It serves as an agentive complement in passive constructions. It's not typically an adverbial, though some might label it as one in certain contexts, especially with predicative verbs.
Clarifying grammatical analysis
The "by trees" phrase in "surrounded by trees" is a prepositional complement, not an adverbial. It’s a complement of the passive verb "surrounded," specifically an agent phrase. In English, it's part of a participial phrase or reduced relative clause. In Chinese grammar, it's often treated as an adjunct, but technically, it’s more of a complement in this case.
Explaining "surrounded by"
The phrase "The house is surrounded" could work, but it sounds odd because "surround" needs two arguments: X and Y. In passive voice, the "by" phrase is optional but usually present. It's not adjunct but a complement, specifically an “agentive by-phrase.” When used adverbially, like in "He walked surrounded by bodyguards," it’s an adjunct that describes the subject’s circumstances.
Clarifying the grammar function
At the phrase level, "by trees" is a complement of "surrounded." At the sentence level, the entire phrase can function as a postnominal modifier ("a house surrounded by trees"), a subject predicative complement ("The house is surrounded by trees"), or an adverbial ("He walked, surrounded by friends"). It's a complement, not an adverbial. You can test by asking if "by trees" can be omitted—if it can, it's still considered a complement.
Thought for 39s
