Irregular nouns and their plurals


You have, I hope, already experienced the irregular verbs, but perhaps not so common are the irregular nouns. 


Below are a list of nouns in their singular form. Some of them you perhaps already know from examples featured in the book. What is the plural form?


Example: One goose, two geese.


1. datum

2. cactus

3. deer

4. fungus

5. foot

6. analysis

7. crisis

8. agenda

9. thesis

10. bacterium

11. appendix

12. woman

13. referendum

14. bureau

15. child

16. man

17. ox

18. medium

19. oasis

20. fish

21. tooth

22. antenna

23. formula

24. mouse

25. bus

26. die

27. elf

28. life

29. moose

30. person

Irregular nouns and their plurals: answers


The answers are marked in red. But there are a few extra notes as well to read to show that it is not always clear. Any examples in brackets are usually the second most popular form of plural.


1. datum/data (However, the word data is being increasingly used as an irregular plural form, as in this example: Customer data is easy to get.)

2. cactus/cacti (or cactuses)

3. deer/deer

4. fungus/fungi (or funguses)

5. foot/feet

6. analysis/analyses

7. crisis/crises

8. agenda/agendas (Okay, this is not really an irregular plural, but originally agenda was the plural of agendum, meaning ‘a thing to be done’, which is no longer used. It now means a list of things to be done, and has become a singular regular noun - the plural now being, of course, agendas.)

9. thesis/theses

10. bacterium/bacteria (This is an interesting one. Strictly speaking, bacteria is already plural - particularly in scientific use and in teaching - meaning many bacterium, but is often used both as uncountable nouns: 'bacteria is nice' and countable: 'bacteria are horrible'. However, bacteria as a regular countable noun is often used in regular speech and in journalism, so it would not be unusual to see or hear bacterias.)

11. appendix/appendices (or appendixes)

12. woman/women

13. referendum/referendums (or if you want to follow Latin rules, referenda

14. bureau/bureaus (or if you follow French rules, bureaux)

15. child/children

16. man/men

17. ox/oxen

18. medium/media (or mediums)

19. oasis/oases

20. fish/fish (or fishes)

21. tooth/teeth

22. antenna/antennae (or antennas)

23. formula/formulas (or formulae)

24. mouse/mice (or mouses if you are talking about the small device that controls the cursor on your computer)

25. bus/buses

26. die/dice (a die is one cube that has dots on each face and is used to play games. But quite often dice is used to describe only one die.)

27. elf/elves

28. life/lives

29. moose/moose

30. person/people (but persons is used in formal contexts)

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