Using prefixes

Home learning focus

To demonstrate understanding of the prefixes mis-, dis-, un- and in-.

This lesson includes:

  • two videos to show you how to use prefixes correctly

  • three activities


Prefixes are groups of letters that are added to the start of words to change their meaning.

Watch this clip to learn more about prefixes.

See some examples of how prefixes can change the meaning of words.

Most prefixes mean a similar thing when they're added to different words.

  • un- and in- usually mean ‘not’.

For example: unhappy, unlocked, unfair and intolerant, incapable, inconsiderate

  • dis- and mis- usually have negative meanings.

For example: disagree, disobey, misbehave, mislead

  • re- usually means ‘again’ or ‘back’.

For example: redo, reappear, redecorate

  • sub- usually means ‘under’.

For example: subheading, submarine

There are spelling rules to follow when you add prefixes to words.

Watch this clip to learn to learn more about these rules and see some examples.

Find out about the spelling rules to follow when using prefixes.

Remember: 'Root words' are the basic words that are used to form other words. Root words haven't had any prefixes or suffixes added to them yet.

Not all prefixes can be added to all root words. You have to choose the correct one.

For example: un- can be added to 'happy' to make 'unhappy', but dis- or mis- couldn't.

Adding in- can be particularly tricky. There are three rules to remember.

1. When the root word begins with an l, the prefix in- changes to il-.

For example: il + legal = illegal

2. When the root word begins with an r, the prefix in- changes to ir-.

For example: ir + regular = irregular

3. When the root word begins with an m or a p, the prefix in- changes to im-.

For example: im + possible = impossible


You may need paper and a pen or pencil for some of these activities.

Activity 1

Complete the prefixes quiz. Can you get all five answers correct?

Activity 2

Complete this ‘Prefix Sort’ activity sheet by matching the root words in the table to the correct prefix.

When you’ve finished, see if you can add one extra word of your own to each column.

Either print out the activity sheet or write your answers in three columns on piece of paper.

Prefix Sort

Activity 3

Add the correct spelling of the in- prefix to the following words.

  • ___active
  • ___clude
  • ___legal
  • ___logical
  • ___regular
  • ___rational
  • ___possible
  • ___mature
  • ___moral

Now choose three words from the list and use each of them in a full sentence.

For example: I was very inactive because I had hurt my ankle.

Where next?

In this lesson you have demonstrated that you can use prefixes.

There are other useful articles on Bitesize to help with your spelling.

There's more to learn

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