What is a suffix?

A suffix is a word ending. It is a group of letters you can add to the end of a root word*
e.g. walking, helpful

*A root word stands on its own as a word, but you can make new words from it by adding beginnings (prefixes) and endings (suffixes).
For example, 'comfort' is a root word. By adding the prefix 'dis' and the suffix 'able' you can make new words such as 'discomfort' and 'comfortable'.

Adding suffixes to words can change or add to their meaning, but most importantly they show how a word will be used in a sentence and what part of speech (e.g. noun, verb, adjective) the word belongs to.

e.g. If you want to use the root word 'talk' in the following sentence:
I was (talk) to Samina.
You need to add the suffix 'ing' so that the word 'talk' makes better sense grammatically:
"I was talking to Samina".

There are various suffixes we use. Probably the most common are 'ed' and 'ing'.
Here are some other suffixes and examples.

Suffix	Example		Suffix	Example
ed	walk + ed = walked		ness	happy + ness = happiness
ing	say + ing = saying		al	accident + al = accidental
er	tall + er = taller		ary	imagine + ary = imaginary
tion	educate + tion = education		able	accept + able = acceptable
sion	divide + sion = division		ly	love + ly = lovely
cian	music + cian = musician		ment	excite + ment = excitement
fully	hope + fully = hopefully		ful	help + ful + helpful
est	large + est = largest		y	ease + y = easy

NB: Adding a suffix to some root words will change the spelling of the new word. There are some spelling rules to help you learn why and when this happens.

Suffix spelling rules - double letters

Usually when you add a suffix to a root word the spelling of both stays the same:
e.g. care + ful = careful
But there are several important groups of words where the spelling of the root word changes when you add a suffix.

Sometimes the spelling changes because of the 'Doubling' rules.
As always, there are exceptions to these 4 rules, but they are a good starting guide:

1] For most short (one syllable) words that end in a single consonant (anything but 'a', 'e', 'i', 'o', 'u') you need to double the last letter when you add a suffix: e.g. run + ing = running sun + y = sunny If the word ends with more than one consonant, you don't double the last letter: e.g. pump + ed = pumped sing + ing = singing

2] For most longer (more than one syllable) words that end in 'l' you need to double the 'l' when you add the suffix: e.g. travel + ing = travelling cancel + ed = cancelled

3] For most longer (more than one syllable) words that have the stress on the last syllable when you say them AND end in a single consonant (anything but 'a', 'e', 'i', 'o', 'u') you need to double the last letter: e.g. begin + er = beginner prefer + ing = preferring If the word has more than one syllable and ends in a single consonant, but the stress isn't on the last syllable, then you don't need to double the last letter before adding a suffix: e.g. offer + ing = offering benefit + ed = benefited

4] If you have a word ending in a consonant and a suffix starting in a consonant, you don't need to double the last letter of the word: e.g. enrol + ment = enrolment commit + ment = commitment

More suffix spelling rules

'y' to 'i' rule

When you add a suffix to a word which ends in a consonant followed by a 'y', change the 'y' to 'i'. e.g. The word 'happy' ends in 'py'. When you add the suffix 'ness', change the 'y' to 'i' to make the word happiness: happy + ness = happiness. Exceptions to the rule. If you are adding the suffix 'ing' to a word ending in 'y', keep the 'y'. e.g. The word 'copy' ends in 'py'. When you add 'ing' the 'y' doesn't change to an 'i' because you would have 2 'i's together: copy + ing = copying.

Silent 'e' rule

When you add a 'y' or a suffix which starts with a vowel (a,e,i,o,u) to a word which ends in a silent 'e', drop the silent 'e'. Silent 'e' words are ones that end with a consonant and have an 'e' at the end, such as hope, like, love. If you say the word to yourself you don't really hear the 'e' at the end. e.g. The word 'noise' ends in a silent 'e'. When you add the suffix 'y', the 'e' is dropped to make the word, noisy: noise + y = noisy. The word 'like' ends in a silent 'e'. When you add the suffix 'ing', the 'e' is dropped to make the word, liking: like + ing = liking. Exceptions to the rule. If a word ends in 'ce', or 'ge', keep the 'e' if you add a suffix beginning with either an 'a', or an 'o'. (This is done to keep the 'c' or 'g' sounding soft.) e.g. The word 'peace' ends in 'ce'. When you add on the suffix 'able' the silent 'e' is kept to make the word, peaceable: peace + able = peaceable

NB: All these rules also apply to words which have a prefix before the root word.
For example if you add the suffix 'ness' to the root word 'unhappy' you would still change the 'y' to 'i': un + happy + ness = unhappiness