How it works
These irregular plurals flashcards put one noun on the front, such as mouse, and its plural on the back: mice. The 60 nouns come in five sets of 12 by pattern, from man and men to cactus and cacti.
Read the full guide
Five patterns, one sheet each
Vowel change and -en holds man, foot, mouse, child and ox. f to ves has leaf, wolf and knife. No change has sheep, deer and species. The last two sets are the Latin and Greek endings: cactus, bacterium and criterion, then crisis, larva and index. Where a second plural is common, such as cactuses or indexes, the back names it and typing either counts.
Print a set, or cut a matching game
Pick a set, turn a card, then press the print button under it: 12 cards on one sheet of Letter or A4, all 60 on 5. Double-sided, flipped on the long edge, mice lands behind mouse. Printed on one side, fronts and backs come out on two pages to cut apart and match.
- Roofs and chiefs keep their f. Two cards in the f to ves set name them as the exceptions.
- Octopus is not in the -us set: the dictionary lists octopuses first.
Questions and answers
What is an irregular plural?
A plural that is not made by adding -s or -es. The noun changes a vowel (foot, feet), swaps f for ves (leaf, leaves), stays as it is (sheep) or keeps a Latin or Greek ending (cactus, cacti).
What are 10 examples of irregular plurals?
Man and men, woman and women, child and children, foot and feet, tooth and teeth, mouse and mice, leaf and leaves, knife and knives, sheep and sheep, cactus and cacti.
Is the plural of fish fish or fishes?
Both are in the dictionary, with fish listed first: one fish, two fish.
Why is the plural of mouse mice?
A few nouns keep an Old English way of making the plural, by changing the vowel sound. Mouse and mice, louse and lice, foot and feet, tooth and teeth, goose and geese, and man and men all belong to that group.