Relative pronouns and clauses

Relative pronouns introduce relative clauses. Most relative pronouns refer to the subject or the object of the sentence. Some of them can be omitted.

1. Who is used for people and refers to the subject of the verb and it cannot be omitted.
   That's the man who married my sister
   Who or Whom are used for people and refer to the object of the verb. They can be omitted. Whom is mainly used in formal writing.
   The woman who/whom they interviewed yesterday got the job.
   The woman they interviewed yesterday got the job.
   



2. Which is used for things and animals and refers to the subject or the object of the verb. When it refers to the subject, it cannot be omitted. When it refers to the object it can be omitted.
   The book which is on the table belongs to my teacher.
   The dress which I bought yesterday is too small for me.
   The dress I bought yesterday is too small for me.
   


3. Thatis used for people, animals and things. When it refers to the subject, it cannot be omitted. When it refers to the object of the verb it can be omitted.
   The little girl that is playing outside is my granddaughter.
   The letter that you wrote still hasn't been posted.
   The letter you wrote still hasn't been posted.
   


4. Whoseshows possession. It is used for people, animals and things and it cannot be omitted.
   That's the woman whose house was burgled last night.
   


5. Prepositions are placed before in formal English and at the end of the sentence in informal English.
   It is a problem about which we can do very little.
   It is a problem which I can do very little about.
   

Relative clauses
There are different kinds of relative clauses

1. Defining relative clauses
2. Non-defining relative clauses.
3. Relative clauses without a pronoun

1. Defining relative clauses give information that helps identify the person, animal or thing the speaker or writer is referring to.
   Which person is your father? The man who is standing near the door.
   The cake (which) I made yesterday is far too sweet.
   We can use that instead of who or which in defining relative clauses.
   Do you know the man who/that sat next to us yesterday?
   


2. Non-defining relative clauses give additional information about a person, animal or thing.
   Rachael, who has just graduated as a doctor, is going to work in India.
   "Who has just graduated as a doctor" adds extra information about Rachael. It doesn't define Rachael, we already know who she is.
   We can leave out the non-defining clause and still have a sentence which means something.
   We cannot use that to replace who or which in non-defining relative clause.
   There is a comma before and after a non-defining relative clause.
   Non-defining relative clauses are rather formal and used mainly in written English.
   In informal spoken English, we usually use two main clauses.
   


3. Relative Clauses without a relative pronoun
   We can use the infinitive instead of a relative pronoun and verb
• after the first, second etc and the next
  Guy was the first person to arrive at the party and the last one to leave.
• after the only.
  Jill was the only member of her family to graduate.
after superlatives
The most adorable present to give your child is a kitten



4. Relative Clauses without a relative pronoun
   We cam use the ing form instead of a relative pronoun and an active verb.
   People wanting more information should go to the inquiry desk.
   We can use the ed form and a passive verb instead of a relative pronoun.
   Fish cooked in white wine tastes delicious