5. Grammar: Relative Clauses

In the previous task, you could see that in fact no mechanical parts of the ABS system were faulty and only a simple software fix was enough to solve the problem. Grammatically, there are several ways to express what was done to find the problem:

Two separate sentences

Two separate sentences

Tests have been carried out successfully. They (These tests) confirm that all components are working properly.

ABS stands for “anti-lock braking system”. It (ABS) is a standard part of every car. 

Tests have been carried out successfully. This (The result of these tests) confirms that all components are working properly.

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Relative Clauses

1) Tests which confirm that all components are working properly have been carried out successfully.

2) ABS, which stands for “anti-lock braking system”, is a standard part of every car.

3) Tests have been carried out successfully, which confirms that all components are working properly.

Study the numbered boxes in the table above and try to answer the following questions: 

  1. Why is there no comma in sentence 1?

  2. Why are there commas in sentence 2?

  3. Why is there a comma in sentence 3?

  4. Which box refers to ABS only, i.e. to one word in the main clause?

  5. Which box refers to tests only, i.e. to one word in the main clause?

  6. Which box refers to the result of the testing process, i.e. to the whole clause describing the fact that the tests have been carried out successfully?

Here you can see short answers to the questions above:

  1. This is because this clause is a defining clause. 

  2. This is because this clause is a non-defining clause that gives extra information. 

  3. This is because this clause is a non-defining clause that gives extra information. 

  4. Sentence in box 2.

  5. Sentence in box 1.

  6. Sentence in box 3.

 

When studying the three relative clauses in the table above, you can see that sentences 2 and 3 have commas, while sentence 1 doesn´t. In English, some relative clauses have commas, but some do not, depending on their type: either a defining relative clause or non-defining relative clause. Make sure you are aware of these two basic types of relative clause by going through this document. You are not only going to read about commas used with relative clauses, but also have the opportunity to revise the rules of the use of the relative pronouns. After going through the grammar overview, practise the relative pronouns here and here. Then practise the use of commas in this task.