In this sentence, what part of speech is 'frightening':
"Halloween can also be frightening for pets."
Is it a participle? Or is it acting as a verb?
English Language Learners Stack Exchange is a question and answer site for speakers of other languages learning English. It only takes a minute to sign up.Sign up to join this community
Frightening is an adjective. There is a natural process in which participles (which can be used as modifiers) become fixed as adjectives. It can be confusing when you try to parse a sentence. However if you check a dictionary you will find "frightening" listed as an adjective.
In a simpler example
Dracula is a frightening monster (adjective)
Dracula is frightening. (probably an adjective)
But if there is a direct object, it must be a verb.
Dracula is frightening the boys. (present continuous of verb "to frighten")