The Grammaring Guide to English Grammar with Exercises

What is a relative clause?

Defining and non-defining relative clauses refer to preceding nouns and are introduced by the pronouns who, whom, whose, which or that. Relative clauses usually come after the nouns that they describe:

The woman

who answered the door

was about forty years old.

Warsaw,

which is the capital of Poland

, lies on the Vistula River.

Sentential relative clauses do not refer to preceding nouns but comment on what has been said before:

I didn't take any waterproof clothing with me,

which was a mistake

.

In relative clauses, we do not use personal pronouns to refer to the nouns described:

*The

woman who she

answered the door was about forty years old.

The

woman who

answered the door was about forty years old.

*

Warsaw, which it

is the capital of Poland, lies on the Vistula River.

Warsaw, which

is the capital of Poland, lies on the Vistula River.