adjective clause

A clause is a group of words that contains a subject and a verb.

An adjective clause is a clause that acts as an adjective. That is, it modifies the noun or pronoun that comes before it:

• Dr. Bondar, who went into space in 1992, was our first female astronaut.
  [clause modifies noun Dr. Bondar]
• Anyone who is afraid of doing too much will end up doing too little.
  [clause modifies pronoun anyone]

The three most common adjective clause signals

Most adjective clauses start with the relative pronouns which, who or that.

• This payment, which is due on Tuesday, should arrive on Monday.
• The person who stole my purse will get a bottle of water, three bandaids, a used kleenex and half a veggie burger.
• The jacket that I bought last week is already missing a button.

Relative pronouns can act as a subject or an object in the adjective clause. (For instance, in the examples above, the pronouns which and who are the subjects of the verbs is and stole, while that is the object of the verb bought.)

We sometimes omit that when it is the object of a verb or preposition:

• The jacket I bought last week is already missing a button.
  [= that I bought last week; that is object of verb bought]
• I can’t find the envelope I put the cheque in.
  [= that I put the cheque in; that is object of preposition in]

For more information on relative pronouns, see the article relative pronouns, who, whom, whose, which, that.

Other adjective clause signals

The relative adverbs when, where and why can also start an adjective clause:

• Noon is the hour when the sun is overhead. [clause modifies noun hour]
• The shop where we bought the camera was near the bridge. [clause modifies noun shop]
• I don’t know the reason why Michel was late. [clause modifies noun reason]

For information on how to punctuate adjective clauses, see the article commas with adjective clauses.