Please read the blog post naturally. It is available at https://dictionaryblog.cambridge.org/2017/10/18/feet-knives-and-sheep-forming-plurals-in-english-1/. You may feel it easier to read the post there. Thank you!
Feet, knives and sheep: Forming plurals in English 1
By Liz Walter
For the majority of words in English, forming the plural is easy. All you need to do is add ‘s’. If the word ends in s, x, z, ch, or sh, you add ‘es’, otherwise it will be impossible to say. So, for example, we get tables, birds, and teachers, or boxes, churches, and dishes.
However, as with most rules in English, there are lots of exceptions. I’ll start with some really common words that have irregular plurals. If you only have time to learn a few, learn these:
+ child > children
+ man > men
+ woman > women (remember the pronunciation is / ˈwɪm.ɪn /. I know it sounds unlikely, but trust me, it’s true!)
+ foot > feet
+ tooth > teeth
An interesting one is person > people. “Persons” is sometimes used in very formal contexts, such as legal documents, but “people” is by far the most common plural, and the one you need to use in 99% of cases.
There are a few other general rules that are worth learning. Firstly, if a word ends in a consonant sound + y, we drop the -y and add -ies. If it ends in a vowel sound + y, we just add -s in the usual way. So we have baby > babies, family > families, city > cities, and company > companies but donkeys, chimneys, runways, and birthdays.
Secondly, words ending in -f or -fe usually drop the -f and add -ves, for example knife > knives, leaf > leaves, life > lives, wife > wives, shelf > shelves. One exception to this is “roofs”. The plural “rooves” used to be used, but “roofs” is the accepted form now – nobody seems to know why this word changed while most other -f or -fe words didn’t!
Words that end in o usually simply add s, e.g. avocados, bistros, discos. However, a few end with -oes and you just have to learn which ones they are. Four of the most common are echoes, heroes, tomatoes, and potatoes. And just to complicate things even further, a few words ending in -o can form their plurals either way, e.g., mosquitos/mosquitoes, mangos/mangoes, volcanos/volcanoes. If you’re not sure, check in a dictionary.
Oddly, a few words don’t change at all from singular to plural. So we can have one or lots of species, sheep, aircraft, deer or series.
Finally, a word of warning. Never, never, NEVER be tempted to use an apostrophe in a plural! It is wrongly used all over the place, especially in shops and cafés. ‘Potato’s’, ‘apple’s’, ‘ice cream’s’ – all of these are wrong and you will lose marks for writing them in an English exam.
That’s a look at the basic rules of plurals. But what about the more complicated ones? Is it terminus or termini? And why is the plural of ‘formula’ formulae? For more complex plurals see my next post.
