Commas and Clauses

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Do you find commas confusing? Don’t worry – you’re not alone. Commas have a variety of functions yet many people are uncertain of how to use them. So far this year we’ve looked at how to use commas as part of a list and how to use commas in direct speech. Today we’re taking a look at how to use commas between clauses.

What is a clause?

A clause is a group of words containing a verb that can either stand alone as a complete sentence or make up part of a more complex sentence. Complex sentences are usually split into main clauses and subordinate clauses.

Subordinate Clauses

A subordinate clause doesn’t make sense on it’s own – it needs the main clause to add meaning to it. Adding a comma between a main clause and a subordinate clause often helps make a sentence as clear as possible. Commas also help indicate when to take a ‘breath’ when reading a sentence.

Here are some examples of subordinate clauses:

  • Having putting it off all day, she finally sat down to do her homework.
  • After we finished work, we counted how much money we made.

There are different types of subordinate clauses and the importance of a comma depends on the type. Conditional Clauses A conditional clause describes something that is possible or probable. It usually begins with ‘if’ or ‘unless’.

Here are some examples of conditional clauses:

  • If it rains, we will have to postpone the picnic.
  • Unless there are train delays, we’ll arrive at four o’clock in the afternoon.

The commas make these sentences clearer but they don’t affect their meaning.

Relative Clauses

A relative clause follows a word like ‘that’, ‘when’, ‘where’, ‘which’, ‘who’, ‘whom’, or ‘whose’ and adds extra information to a sentence. If the information being added is interesting but not essential, a comma often adds clarity to the sentence. These types of clause are known as a non-restrictive relative clause.

Here are some examples of non-restrictive relative clauses:

  • My mother went to Venice, where she enjoyed exploring the canals and eating spaghetti.
  • I celebrated my birthday with my cousins, who I hadn’t seen in years.

If a non-restrictive relative clause is in the middle of a sentence, you should use a comma both before and after it. For example:

  • Thomas, who I have known for ten years, came to visit.

In some sentences, however, the relative clause adds essential information. Without this information, the sentence wouldn’t make sense. These sentences are known as restrictive relative clauses and you should not put commas before or after them.

Here are some examples of restrictive relative clauses:

  • I hate the man who lives across the street.
  • Guests who have special passes can skip to the front of the queue.

If you found this article useful, why not have a look at some of our other posts about punctuation?

Have a great week!


03 Jul 2017
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