I usually start teaching vocabulary building with suffixes because we are so used to adding suffixes to our words.
As an example, take the noun girl. What if you want to change the word to refer to more than one girl (to make it plural)? How do you do that?
Yes! You add the suffix -s. The word becomes girls.
Say you see a fox run through your yard! What if, while standing at your window, you see a second fox? How do you tell someone you saw both of them running through your yard?
Yes! You add the suffix -es. You say you saw two foxes running through your yard.
(You can review how to make words plural here.)
That’s all a suffix is: an ending added to a word. Plural suffixes are incredibly common. But we have so many others. Say you walk out to the mailbox and check the mail today. What if your mom comes home from work and doesn’t know you did and she checks the mail, too? So you tell her you will be checking the mail every day for the next week, but you forget on Friday and Saturday. What do you say when she asks you if you checked the mail?
See? You also add suffixes to verbs to change verb tense. Generally we add -ed to the end of a verb to show that the item happened in the past–to show past tense. But we can also add -ing as a suffix to a verb and change the tense. (You can review verb tenses here.) We can even make a verb a noun or an adjective in the process!
Extra credit: We call verbs transformed into nouns or participles with an -ing suffix gerunds or participles, depending on whether they are functioning as nouns or adjectives. (These are called verbals, and you can review them here.)
To summarize, endings added to words are called suffixes, and some of the most common suffixes are used to pluralize nouns (or to make a word refer to more than one item) or conjugate verbs (to make a verb agree with its noun and be the appropriate tense).
One final note: If you struggle with grammar, suffixes can help you determine what parts of speech certain words are. For example, if a word ends in -ence, -ism, -ency, or -archy, it’s likely to be a noun (and an abstract one at that).
What’s next? Suffixes you should know.
