Language Arts Canadian Lead Primary School

Suffixes Part One: Inflectional Suffixes

Suffixes Part One: Inflectional Suffixes

The word suffix actually has a chameleon prefix. Can you spot it?

suf- is a version of sub-, but since -fix- begins with a fricative (manner, not placing this time), old sub- becomes the new and improved suf-.

Sub- means “under”, that’s what everybody knows, but under also has the meaning of “secondary/after”. So why is the word suffix built like it is?

A suffix is a letter or letters placed after a base to change that base’s meaning. The thing I really, really want you to understand about suffixes, though, is that they only have TWO jobs. That’s it. But you will not understand them fully if you don’t understand your parts of speech and syntax.

Here are the two things suffixes do…

They tell us a bit more information about the base. In posh terms, they help the base inflect, that is to bend. The base is still the base, doing its basey thing and remains the same part of speech, it’s just that if it needs to express precisely how many, who did the thing or even when, it needs a suffix to help it.

This is where an inflectional suffix comes in.

The terrific news here is that there are only eight inflectional suffixes in English. All the rest are the other type, which we will get to shortly.


Here’s the big eight:

  1. The plural suffixes (-s, -es, -en, -ae, -i)

Nouns have two ways of changing and still being nouns. They can change their number by adding a plural suffix.

Dog becomes dogs.

Fox becomes foxes.

Child becomes children.

Antenna becomes antennae.

Fungus becomes fungi.



  1. Apostrophe <s> (-‘s)

Nouns can have a suffix that shows they own or have a very close relationship to another noun. That suffix is apostrophe + <s>: -’s

The dog owns a bone, it is the dog’s bone.

A hard day’s night – not ownership but very close relationship.


Easy if this suffix is not taught as some kind of punctuation mark.

Verbs can also change and remain as verbs:

  1. Third person singular present tense: -s

When he, she or it is does or has something, your verb should end with an -s.

He sits.

She stands.

It howls.


So three of our inflectional suffixes contain the letter <s>. No wonder people get confused!

  1. Past tense (-ed)

Usually, we use the suffix -ed. However, there are verbs that don’t do this and they are known as irregular verbs. Because learning the grammar of your native language is biologically primary, getting to grips with irregular verbs is something that typically developing children do without explicit instruction.

This means that irregular verb instruction tends to be left out of mainstream curricula, which is understandable. However, there are children who have developmental language disorders and therefore do not learn irregular verbs as readily as their typical peers.

It’s a good thing to check this wherever possible. The other good thing is that it’s not too difficult to acquire, once explicitly taught and practised.

There are hundreds of irregular verb lists ready available online. Pick one and work your way through it. Examples below:

Irregular: He sat.

Irregular: She stood.

Regular: It howled.

  1. Present participle (-ing)

These verbs end with -ing and indicate that the be/do/have in a sentence is happening at the same time as the utterance. Compare he walked to he is/was walking.

  1. Past participle (-en)

When a verb takes the suffix -en with have, it indicates past tense and passive voice.

Past tense:

They have stolen my bike.

She has forgotten the keys.

Passive voice:

My bike has been stolen.

The keys were forgotten.


Adjectives can also have suffixes added:

  1. Comparative

When comparing one thing to another, the suffix -er is often added to the adjective:

Some girls are bigger than others.

  1. Superlative

In a comparison of more than two, the most extreme takes the suffix -est:

The greatest show on Earth.

Key inflectional suffixes

The grammar and syntax scope and sequence in Langauge Arts offers suggestions about where and when to introduce the various inflectional suffixes.

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