Irregular Plurals: Foot → Feet, Goose → Geese
Quick Answer
A small group of very old English words change the vowel inside instead of adding an ending: one foot, two feet; one tooth, two teeth. There are only eight of them in everyday English — and you already know most.
See the Pattern First
Listen to the vowel change in the middle of each word.
- One foot hurts. Both feet hurt.
- A goose is on the lake. Six geese are on the lake.
- One tooth is loose. My teeth are fine.
- That man is waiting. Those men are waiting.
Notice that nothing is added to the end. The change happens inside the word — oo becomes ee, a becomes e. Linguists call this a vowel shift, and it is over a thousand years old.
The Complete List — Only 8 Words
This really is the whole set in normal English. Learn these eight and you are done.
| One | Many | One | Many |
|---|---|---|---|
| foot | feet | goose | geese |
| man | men | ox | oxen |
| tooth | teeth | child | children |
| mouse | mice | woman | women |
These come up often, so they have their own full lesson with more practice: the plural of child and the plural of mouse and the plural of woman.
Why Only These Words Survived
A thousand years ago, many more English nouns worked this way. Over time, speakers replaced the odd forms with the easy -s ending, because -s is simpler. The words that survived are the ones people used every single day — parts of the body, family, farm animals. High use protects irregular forms.
That is why you will never meet a new word in this group. No modern word joins it. The list is closed, which makes it one of the safest things to memorise in English.
The vowel changes. Nothing is added.
Two Odd Ones Out
Two members of this group do not change their vowel:
- child → children — it adds a whole syllable, -ren.
- ox → oxen — it adds -en. This is the last surviving -en plural in English.
“Oxen” is the final trace of an ending that once covered dozens of words. You are looking at a museum piece.
Mistakes Learners Make (You Are Not Alone)
The most common errors are the “double plural” — changing the vowel and adding -s:
- ✗ two feets → ✓ two feet (feet is already plural)
- ✗ many childrens → ✓ many children (children is already plural)
- ✗ three mouses → ✓ three mice (but computer “mouses” is accepted by some)
Doubling the plural is the single most common mistake here, and it happens because your brain wants to mark “many” twice. Once is enough.
Your Turn — Quick Quiz
Five questions. Take your time — the table above is still there if you need it.
1. 1. My new shoes hurt both ____.
2. 2. The dentist checked all my ____.
3. 3. There are twenty ____ in the classroom.
4. 4. Two ____ pulled the heavy cart.
5. 5. Five ____ were waiting outside.
Keep Going
Eight words, one thousand years of history, and now you know the whole set.
Next comes a group where English cannot make up its mind. Potatoes has an e. Photos does not. Both end in -o. What decides it?
Next lesson: Words ending in -o: potatoes or potatos?
Sources
I’m Khamis Maiouf. English is not my first language – I learned it as an adult in the UK, passed Functional Skills Level 2 in English, qualified in Hairdressing at Level 3, and I’m now studying Business at university. For over five years I’ve taught ESOL classes in my community and tutored students through GCSE English. I write every lesson on this site myself, for the learner I used to be.
