The Grammaring Guide to English Grammar with Exercises

Non-defining relative clause

A non-defining relative clause describes a preceding noun by adding extra information about it. The noun has a clear reference (it is clear who or what we are talking about) even without the clause:

The Mona Lisa was painted by Leonardo da Vinci,

who was also a prolific engineer and inventor

.

The human heart,

which has a mass of about 300 grams

, pumps blood throughout the body.

A non-defining relative clause can also continue a story by saying what happened next:

I called my mother,

who became very upset

.

(I called my mother, and she became very upset.)

The non-defining relative clause is separated from the rest of the sentence by commas (,). In speech, we make a short pause before and after the clause.

Quotes:

The true meaning of life is to plant trees, under whose shade you do not expect to sit. - Nelson Henderson