What’s the Plural of Knife? Understanding English Irregular Plurals
Quick Answer
The plural of knife is knives. The word “knifes” is not correct.
One: I need a sharp knife.
More than one: Put the knives in the drawer.
Knife Becomes Knives — See the Pattern
Look at these words. Can you see what happens?
- one knife → two knives
- one wife → two wives
- one life → two lives
- one leaf → two leaves
Did you see the pattern? The -fe at the end changes to -ves. This is a rule in English for many words that end in -f or -fe.
| One (singular) | More than one (plural) |
|---|---|
| knife | knives |
| wife | wives |
| life | lives |
| leaf | leaves |
| wolf | wolves |
Why Knives and Not Knifes
In English, most words that end in -fe change to -ves when you make them plural:
- knife → knives (not “knifes”)
- wife → wives (not “wifes”)
- life → lives (not “lifes”)
You cannot just add an -s to “knife.” The word “knifes” does not exist as a plural in English. You must change the -fe to -ves.
Easy way to remember: Think of wife → wives. Most people know that one. The word knife follows the same pattern: knife → knives.
What about words like roof and chef? Not all words that end in -f follow this rule. Words like roof → roofs and chef → chefs just add an -s. But for knife, it is always knives.
The Rule in One Line: Knife ends in -fe, so the plural is knives (-fe → -ves).
How to Use Knives in Everyday English
- Please put the knives and forks on the table. (more than one knife)
- Be careful — those knives are very sharp. (more than one)
- I need a knife to cut this bread. (just one)
- The chef uses different knives for different foods. (more than one)
- Can you pass me that knife, please? (just one)
You are doing great. Now let’s look at the mistakes many learners make with this word.
The Most Common Mistake With Knife
Even advanced learners write “knifes” sometimes — so if you have made this mistake, you are not alone. It feels like adding an -s should work, but English has other plans for this word.
Mistake: Writing “knifes” instead of “knives”
✗ We need more knifes for the dinner party.
✓ We need more knives for the dinner party.
✗ She washed all the knifes after cooking.
✓ She washed all the knives after cooking.
✗ The shop sells knifes of all sizes.
✓ The shop sells knives of all sizes.
How to remember: The word “knife” ends in -fe. In English, -fe always changes to -ves in the plural. No word that ends in -fe just adds an -s. Think: knife → knives, wife → wives, life → lives. They all work the same way.
Other words like this: wife → wives, life → lives, wolf → wolves, leaf → leaves, half → halves.
Test Yourself: Knife or Knives?
Choose the correct answer for each sentence. Click Check to see if you are right.
1. Please put the _______ on the table for dinner.
2. I need a _______ to cut this apple.
3. The chef keeps all his _______ very sharp.
4. Can you pass me that _______? I want to cut the cheese.
5. She bought three new _______ for the kitchen.
Keep Going — You Are Building Something
You just learned that knife becomes knives. That is one more plural you will never get wrong again.
But here is something interesting — the word leaf also ends in -f. You see leaves on trees every day. So what happens when you write about more than one? Is it “leafs” or “leaves”? And does the same -f → -ves rule always work?
Next lesson: What Is the Plural of Leaf?
Sources
My name is Khamis Maiouf. I am the creator of the English Teacher Site, dedicated to providing valuable resources and insights for students around the world. With a passion for education and a commitment to helping students enhance their skills, I aim to make English teaching more effective and enjoyable for both educators and students.
