the more formal I saw the boy about whom you are talking. The relative clause functions as an adjective, answering questions such as "what kind?", "how many?" or "which one?" The adjective clause in English will follow one of these patterns: Relative Pronoun [Functioning as Object of Verb] + Subject + Verb This is the ball that I was bouncing. Relative Pronoun [Functioning as Object of Verb] (Omitted but Implied) + Subject + Verb This is the ball I was bouncing. Relative Adverb + Subject + Verb (possibly + Object of Verb) That is the house where I grew up. That is the house where I met her. Relative Pronoun [Functioning as Subject] + Verb (possibly + Object of Verb) That is the person who hiccuped. That is the person who saw me. Relative Pronoun [Functioning as Object of Preposition] + Subject + Verb (possibly + Object of Verb) + Preposition That is the person who(m) I was talking about. That is the person who(m) I was telling you about. Preposition + Relative Pronoun [Functioning as Object of Preposition] + Subject + Verb (possibly + Object of Verb) That is the person about whom I was talking. That is the person about whom I was telling you. Possessive Relative Pronoun + Noun [Functioning as Subject] + Verb (possibly + Object of Verb) That is the dog whose big brown eyes pleaded for another cookie. That is the dog whose big brown eyes begged me for another cookie. Possessive Relative Pronoun + Noun [Functioning as Object of Verb] + Subject + Verb That is the person whose car I saw. For a discussion of adjective clauses in languages other than English, see Relative clause#Examples. Punctuation English punctuation The punctuation of an adjective clause depends on whether it is essential (restrictive) or nonessential (non-restrictive) and uses commas accordingly. Essential clauses are not set off with commas; nonessential clauses are. An adjective clause is essential if the information it contains is necessary to the meaning of the sentence: The vegetables that people often leave uneaten are usually the most nutritious. The word "vegetables" is non-specific. Accordingly, for the reader to know which are being mentioned, one must have the information provided in the adjective clause (in italics). Because it restricts the meaning of "vegetable", the adjective clause is called a restrictive clause. It is essential to the meaning of the main clause and