what is a complements
There are various types.
http://www.answers.com/topic/complement-linguistics
On that webpage, there's an overall definition. Then go into the Contents section to read about the different kinds of complements.
One main thing is to remember that this word is related to the word "complete." (It has nothing to do with telling someone how good they look!)
In grammar, a complement is a word or a group of words that completes the meaning of a sentence. It provides additional information about the subject, object, or verb in the sentence. Complements can be divided into two main types: subject complements and object complements.
1. Subject Complement: A subject complement follows a linking verb and provides more information about the subject of the sentence. It can either be a predicate adjective or a predicate nominative.
- Predicate Adjective: It describes or modifies the subject. For example: "She is happy." The word "happy" is a predicate adjective complementing the subject "she."
- Predicate Nominative: It renames or identifies the subject. For example: "He is a doctor." The word "doctor" is a predicate nominative complementing the subject "he."
2. Object Complement: An object complement follows and modifies a direct object. It provides more information about the direct object of the sentence. It can be a noun, pronoun, or adjective.
- Noun/Object Complement: It renames or identifies the direct object. For example: "They made John the captain." The phrase "the captain" is a noun/object complement modifying the direct object "John."
- Adjective/Object Complement: It describes the direct object. For example: "They painted the house red." The word "red" is an adjective/object complement modifying the direct object "house."
Identifying complements in a sentence involves determining the relationships between verbs, subjects, and objects. Look for linking verbs (e.g., is, became) or verbs that are used transitively (require a direct object). Then, analyze how the complement relates to the subject or object to understand its function in the sentence.