1. 112 Najd

2.  A restrictive relative clause provides essential information. (No commas used)

3.  It reminded him of the house. [which house?]  It reminded him of the house that he used to live in.

4.  The tickets had all been sold to the fans who arrived before noon.  This sentence implies the existence of other fans who arrived after noon and couldn't buy tickets.

5.  The passenger who was wearing her seatbelt wasn't injured when the car skidded into the phone pole.  This sentence implies that there was another passenger who wasn't wearing a seatbelt and was injured.

6.  Lyle's brother who lives in Detroit is an engineer.  Again, this sentence implies the existence of someone else: apparently Lyle has another brother who does not live in Detroit.

7.  A non-restrictive relative clause provides information that can be left out without affecting the meaning or structure of the sentence. (Commas are used)

8.  The items, which are believed to be very old, included a grandfather clock worth around £3,000.  The items included a grandfather clock worth around £3,000.

9.  The Titanic, which sank in April 1912, is the subject of a recent movie.

10.  Is the following sentence punctuated correctly?  Only people, who speak Russian, should apply for the job.

11.  Incorrect!  Only people who speak Russian should apply for the job. √

12.  Do the following sentences contain restrictive clauses or non-restrictive clauses?

13.  My brother who lives in Ohio is a civil engineer.

14. Restrictive

15.  My brother, who lives in Virginia, is a rocket scientist.

16. Non-restrictive

17.  The book that is lying on the coffee table belongs to Cherie.

18. Restrictive

19.  The book, which is lying on the coffee table, belongs to Cherie.

20.  Non-restrictive