Defining and non-defining relative clauses

Relative clauses are dependent clauses that provide additional information about a noun in the main clause. They begin with a relative pronoun (who, whom, whose, which, that) or a relative adverb (when, where, why).

There are two main types of relative clauses:

1. Defining Relative Clauses

Defining relative clauses give essential information about a noun. Without this information, the sentence's meaning would be unclear. These clauses are not separated by commas.

The book that I borrowed from the library was excellent.

In this sentence, the relative clause "that I borrowed from the library" specifies which book is being referred to. Without it, the sentence would be incomplete.

Relative Pronouns Used in Defining Clauses

• Who – refers to people (subjects)

  The teacher who helped me is very kind.

• Whom – refers to people (objects, formal style)

  The woman whom I met yesterday is a famous writer.

• Whose – shows possession

  The student whose laptop was stolen reported it to the office.

• Which – refers to animals and things

  The laptop which I bought last year is very fast.

• That – can replace "who" or "which" in defining clauses (more common in spoken English)

  The car that he drives is brand new.

Singular vs. Plural for Collective Nouns like "Team"

Some nouns, such as team, family, staff, government, can be singular or plural, depending on whether they are seen as a single unit or a group of individuals:

• Singular meaning (as one unit) → "That" or "Which"

  The team that won the championship celebrated together.

• Plural meaning (as individuals) → "Who"

  The team who are working on the project need more time.

In American English, collective nouns are usually singular, while in British English, they can be singular or plural.

2. Non-defining Relative Clauses

Non-defining relative clauses provide extra, non-essential information. They are always separated by commas.

My sister, who is a doctor, is visiting us.

If we remove "who is a doctor", the sentence still makes sense: "My sister is visiting us". The extra information is not necessary to identify "my sister".

Relative Pronouns Used in Non-Defining Clauses

• Who – refers to people

  My uncle, who lives in New York, is coming to visit.

• Which – refers to things

  The Eiffel Tower, which is in Paris, is a famous landmark.

• Whose – shows possession

  My neighbor, whose dog is always barking, apologized yesterday.

Important Rules for Non-Defining Clauses:

Do not use "that" in non-defining clauses.

The book, that I borrowed, is interesting. (Incorrect)

The book, which I borrowed, is interesting. (Correct)

You cannot omit the relative pronoun in non-defining clauses.

My brother, I saw yesterday, is fine. (Incorrect)

My brother, whom I saw yesterday, is fine. (Correct)

Common Exceptions and Special Cases

1. When to Use "That" Instead of "Who" or "Which"
   • "That" is often preferred in defining clauses, especially in informal speech.
   • "That" cannot be used in non-defining clauses.
2. When You Can Omit the Relative Pronoun
   • In defining clauses, "who", "which", and "that" can sometimes be omitted if they function as the object.

   The book (that) I read was amazing.

   • But they cannot be omitted if they function as the subject.

   The boy who helped me is my friend. (Correct)

   The boy helped me is my friend. (Incorrect)

3. Using "Whom" vs. "Who"
   • "Whom" is technically correct when it functions as an object, but in modern English, "who" is often used instead, especially in speech.

   The woman whom I met is a writer. (Formal)

   The woman who I met is a writer. (Common in speech)

4. Using "Which" for Whole Clauses
   • "Which" can refer to an entire preceding clause, rather than just one noun.

   He forgot his keys, which made him late for work.

   Special Cases: Collective Nouns in Relative Clauses

   Some nouns, such as team, family, staff, government, audience, committee, and company, can be considered singular (as one unit) or plural (as a group of individuals). This affects verb agreement and the choice of relative pronouns like who, which, and that.

   Using the Singular Form

   When referring to the group as a single entity, use "that" or "which" and a singular verb.

   The team that is playing in the final has trained hard.

   My family, which includes five members, is going on vacation.

   The government which is responsible for the decision has made its stance clear.

   Using the Plural Form

   When focusing on the individuals within the group, use "who" and a plural verb.

   The team who are celebrating played really well.

   My family who live in different cities often call each other.

   The staff who work late are dedicated employees.

   British vs. American English Differences

   • In American English, collective nouns are usually singular:

     The government is planning a new policy.

   • In British English, they can be singular or plural, depending on whether the group is seen as a unit or as individuals:

     The government are discussing new policies.

     The government is discussing a new policy.

   Key Rules for Relative Pronouns

   • Use "that" or "which" when referring to the group as a single unit.
   • Use "who" when referring to the individuals within the group.
   • "Police" is always plural:

     The police who are investigating the case have made progress.

   By understanding these distinctions, you can use relative clauses more accurately in different contexts!