I am trying to understand which syntactic role the word red has in this sentence:
We could colour the walls red.
My first thought was it being an adverb, but I have never heard someone saying colours could be used as adverbs. Also, the position is untypical for adverbs.
What part of speech is red in the sentence? What syntactic role does it play? Is it some sort of adjective-valency perhaps? Which other verbs (like to colour) have similar properties?
Best Answer
As BillJ mentioned in the comment, "red" is an adjective functioning as an object (or objective) complement whose primary role is to complement the transitivie verb and its object to show what it has become. For example, "We painted the walls red" could be rephrased to:
There are many transitive verbs that are used in "verb + object + object complement" construction as indicated in the link. You can visit the link and see how it works.
One thing to note is "red" is not an adverb and it doesn't function as an adverb as it doesn't modify the verb or other parts of the sentence.