What is an adjective clause?
An adjective clause (also called adjectival clause) is a dependent clause which modifies a noun and usually begins with a relative pronoun (which, that, who, whom, whose) or a relative adverb (where, when, why).
Students who work hard get good grades.
→ The adjective clause who work hardmodifies the noun students.
The book which you lent me is very interesting.
→ The adjective clause which you lent me modifies the noun the book.
Leila, whose father is a famous poet, invited me to her birthday party.
→ The adjective clause whose father is a famous poet modifies the noun Leila.
My grandmother remembers the days when there were no personal computers.
→ The adjective clause when there were no personal computers modifies the noun the days.
There are two types of adjective clauses:
Restrictive or defining clauses
Non-restrictive or non-defining clauses
Restrictive / Defining Clauses
Restrictive (also called defining) clauses give essential information about the noun. These clauses don’t require commas.
The man who is standing there is a secret agent.
The writer who won the Nobel Prize is from Colombia.
Non-restrictive / non-defining clauses
Non-restrictive (also called non-defining) clauses give extra or non-essential information about the noun. These clauses require commas.
Fast food, which most people love, is not very healthy at all.
My uncle, who is a farmer, lives in the countryside.