###

Relative clauses can be classified into two main types: restrictive (defining) clauses and non-restrictive (non-defining) clauses. These types serve different purposes and have distinct characteristics.

### Restrictive (Defining) Clauses

Restrictive clauses provide essential information about the noun they modify. They are crucial for understanding the meaning of the sentence because they specify or define which particular thing or person is being referred to. Without this clause, the sentence’s meaning would be incomplete or unclear.

**Characteristics:**

– No commas are used.

– The information is essential to the meaning of the sentence.

– Often uses “that” (but can also use “who,” “whom,” “whose,” and “which”).

**Examples:**

1. The **car that is parked outside** belongs to my neighbor.

2. The **students who study hard** usually succeed.

3. The **book which has a red cover** is mine.

4. The **employee whose work is exemplary** will get a bonus.

5. The **restaurant where we ate** was fantastic.

### Non-Restrictive (Non-Defining) Clauses

Non-restrictive clauses add extra information about the noun they modify. This additional information is non-essential, meaning the sentence would still make sense if the clause were removed. These clauses are set off by commas.

**Characteristics:**

– Commas are used.

– The information is extra and not essential to the meaning of the sentence.

– Uses “who,” “whom,” “whose,” and “which” (but not “that”).

**Examples:**

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

2. My **brother, who lives in New York,** is visiting this weekend.

3. Lisa’s **cat, which she adopted last year,** is very friendly.

4. The **conference, where many experts spoke,** was very informative.

5. The **professor, whose research is groundbreaking,** received an award.

### Key Differences

| Feature                           | Restrictive Clauses                           | Non-Restrictive Clauses                           |

|———————————–|———————————————-|————————————————–|

| Importance of Information         | Essential; defining the noun                 | Non-essential; adding extra information          |

| Commas                            | Not used                                      | Used to set off the clause                       |

| Common Relative Pronouns          | That, who, whom, whose, which                 | Who, whom, whose, which (not that)               |

| Sentence Integrity without Clause | Sentence becomes unclear or changes meaning   | Sentence remains clear and maintains meaning     |

### More Examples

#### Restrictive Clauses

1. The **house that Jack built** is falling apart.

2. The **candidate who applied first** got the job.

3. We need to find the **notes which explain this formula**.

Without the restrictive clause, the meaning of the sentence would be incomplete or altered.

#### Non-Restrictive Clauses

1. The **museum, which we visited last year,** is closing down.

2. My **friend Sarah, who is an artist,** is moving to Berlin.

3. Their **holiday, which they planned for months,** was ruined by the storm.

The sentence would still make sense without the non-restrictive clause; the clause only provides additional information.

### Practice Sentences

**Decide if the following sentences are Restrictive or Non-Restrictive:**

1. My **aunt, who lives in Boston,** is coming to visit.

   – **Non-Restrictive** (The information can be omitted.)

2. The **report that you submitted** needs some revisions.

   – **Restrictive** (Essential to identify which report.)

3. The **books, which are on the top shelf,** are mine.

   – **Non-Restrictive** (Additional information, not essential.)

4. The **teacher who teaches math** is very popular.

   – **Restrictive** (Essential to identify which teacher.)

### Summary Table

| Type                          | Usage                            | Example Sentence                                     |

|——————————-|———————————-|——————————————————|

| Restrictive (Defining)        | Essential information            | The **cat that has a white tail** is mine.           |

| Non-Restrictive (Non-Defining) | Extra information (with commas)  | The **cat, which has a white tail,** is very friendly.|

By understanding the differences between restrictive and non-restrictive clauses and knowing how to use them correctly, you can write with greater precision and clarity.