| This article is part of the grammar course.
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The Direct Object (or Od) is a noun, noun phrase or noun clause that follows a transitive verb. Indeed, the very idea of transitivity says that there must be a Direct object after the verb. The Od is the 'thing' (or person or place, etc) on which the action of the (transitive) verb is performed.
Some modern grammarians classify the Direct Object as being a form of the Complement: this is sometimes labelled more precisely the Complement Object Direct or COd.). The name implies that it completes verbs by identifying what or whom they are 'done to' or performed on. In traditional Grammar, this element of the Sentence was called simply the Object.
Examples: "they built a house"; "Parliament passes laws"; "she made a mistake"; "I like him"; "she drives a Mercedes"; "we thought brown, but we chose blue"; etc. Verbs that require this are called transitive.