Fred is the man who cleans the school.

فرد مردی است که مدرسه را تمیز می کند.

The book that you bought gives great information about holidays
►The book you bought gives great information about holidays.

The author who wrote that book did a great job.
► The author wrote that book did a great job.

I saw the author who wrote that book.

My sister, who is from Barcelona, speaks Castellano and Catalan.
Sam, whose father is a doctor, is studying French.
Edinburgh, which is in the east of Scothland, is a beautiful city.
Edinburgh, where we spent our holiday, is a beautiful city.
The accident happened on Tuesday, when I was driving home.