A dependent clause can do an adjective’s job. An adjective clause (also called a relative clause) follows a noun and tells which one or what kind. It usually begins with a relative pronoun: who, whom, whose, which or that (sometimes where or when).
Key idea
An adjective clause comes right after the noun it modifies. Its relative pronoun does a job inside the clause (subject or object) and connects the clause to that noun.
Why it works
Adjective clauses let you combine sentences: “I found a key. You lost it.” becomes “I found the key that you lost.” They also need careful commas: a clause that only adds information is set off with commas (“My uncle, who is a pilot, flew us home”); one that tells which one is not.
Worked example: Find the clause and its noun
“The girl who won the race is my cousin.”
- The clause starts with who: who won the race.
- Inside it, who is the subject and won the verb.
- It tells which girl, so it modifies girl.
Answer: who won the race, modifying girl
Worked example: Not the nearest noun
“The boy with the kite that is stuck in the tree looks sad.” What is stuck?
- The clause that is stuck in the tree follows kite.
- The kite is stuck, not the boy.
Answer: the kite: the clause modifies kite
Common mistake
Ending the clause too early (taking only that you), or attaching it to the wrong noun. Take the whole clause, from the relative pronoun through its verb and everything that goes with it, and look at the noun just before it.
Which or that? American usage guides generally prefer that for a clause that tells which one (“the book that you lent me”) and which with commas for one that only adds information. Using which for the first kind is standard too, especially in British English. Usage and Mechanics goes into the details.