AMELIA: Hello. My name's Amelia. In this video, we will look at how to take words you already know and make them into new words. All you have to do is add a few letters before the word — these are called prefixes — or add a few letters after a word — these are known as suffixes.
Animation of girl holding the words 'prefixes' and 'suffixes' aloft.
AMELIA: Here's an example.
Animation of the word 'place' with prefixes and suffixes
AMELIA: Place. Replace. Replacement. Be careful. You can't do this with all vocabulary. But you can have fun experimenting to see which ones work and which ones don't.
Animation of the word 'do' with prefixes.
AMELIA: Let's look at prefixes first. We all know the word 'do'. Did you know that you can redo something? And if you're not happy with it, you can undo it too. What does the prefix 're-' mean here? That's right. 'Re-' means 'again', so if you redo something, you do it again. And what about 'un-' in 'undo'? 'Un-' is an opposite, so if you undo something, you reverse what you have done. Here's another prefix.
Animation of words and a boy holding a sign with a cross mark
AMELIA: What does it mean? Disagree. Dislike. Disallow. Disappear. 'Dis-' also means 'not' or 'reversal'. Now let's look at some suffixes.
Animation of boy and the word 'happy'.
AMELIA: 'Happy' is an adjective. How can we make it into a noun? Simple. Just add the suffix '-ness'. 'Happy' plus '-ness' equals 'happiness'. Here are two more adjectives to express feelings — 'sad' and 'tired'. To make the noun, you just add the same suffix. Have a look.
Animation of boy with words and suffixes.
AMELIA: 'Sad' plus '-ness' equals 'sadness'. 'Tired' plus '-ness' equals 'tiredness'. There are a few more prefixes and suffixes that go with a range of words. Learning which ones to use and with which words may seem hard at first, but with time, you'll learn to hear what sounds right. Prefixes and suffixes are everywhere. Next time you're reading or listening to English, start noticing which beginnings and endings are being used. Make a note of them, and more importantly, use them. It's the only way to remember them. We hope you found this video helpful and we look forward to your return. Thanks for watching.