The suffix -ion (-tion, -sion)

Learn how we can use the (very useful and very common) suffix -ion to turn many English verbs into nouns.

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The ion suffix video

I have a question. If a word ends in -ion, what kind of word is it? It’s probably a noun, a thing. We often add -ion to verbs to create nouns.


So compete is the verb. We add -ion and we get competition, the act of competing. Persuade is the verb. Add -ion and we get persuasion. The act of persuading.
-ion is a very common suffix and it might be spelled with a t or an s. Let’s look at some more -ion words.

A decision.
Construction. Destruction.

Can you tell if -ion is spelt with a t or an s? No, not really. Sometimes looking at the base verbs can help. So discuss becomes discussion with an s. Meditate becomes meditation with a t. But usually you need to learn the spellings one by one. Check on the web or in a dictionary.
We pronounce this suffix in two ways. Shun and Zhun. So either with an unvoiced sound, sh, shun, or a voiced sound, zh, zhun. Voiced, zhun, decision, zhun. Unvoiced, shun, construction, shun.

An explosion. Vacation.

Unvoiced, shun. Vacation, shun.
Voiced, zhun. Explosion, zhun.
But the really important thing about pronunciation is the rhythm. -ion syllables are always unstressed. It doesn’t matter how long the word is, the syllable in front of -ion gets the stress. So say -ion very quickly and focus on stressing the syllable in front of it. Let’s practise together. Say some words with me.
Action. DA-da. Action. DA-da.
Attention. da-DA-da. Attention, da-DAH-da.
Levitation. da-da-DA-da. Levitation. da-da-DA-da.
Communication. da-DA-da-DA-da. Communication. da-DA-da-DA-da.
Great! To help you get the rhythm of some more -ion words, I’ve made a video of a song for you. Its a classic Beach Boys number with lots of -ion words, so you can watch and sing along. I’ll put the details here and below as well. Or maybe you’d like to learn about another prefix or suffix? If so, click on our prefix and suffixes playlist. And have you subscribed to our channel yet? If you haven’t, make sure you do! You don’t want to miss our next video.

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