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Tricky Plurals

English Stars 20/5/23

When it comes to working with plurals in English, we usually add -s to make a word plural (more than one). While this is the most common rule, there are many exceptions—some of which have their own exceptions within the exceptions. Understanding these rules will help students to tackle the most common plural exceptions.

Rule 1: Add -es

Add -es to words ending in ch, s, sh, ss, x or z, for example:

• beach/beaches
• lens/lenses
• wish/wishes

Exceptions: Be aware of words that don’t follow this rule, such as ox/oxen or axis/axes.

Rule 2: Words ending in f or fe

If a word ends in f or fe, change it to v before adding -es, for example:

• leaf/leaves
• wolf/wolves
• life/lives

Exceptions: Some words don’t follow this rule, such as bank safe/bank safes and handkerchief/handkerchiefs.

Rule 3: Words ending in y

When a word ends in y, and there’s a consonant before it, change the y to an I and add -es, for example:

• baby/babies
• lady/ladies
• fly/flies

Rule 4: Words ending in o

Add either -es or -s to words ending in o, depending on the word. For example: just add -s to these words:

• studio/studios
• kilo/kilos
• photo/photos

Add -es to these words:

• echo/echoes
• tomato/tomatoes

Rule 5: Rules for words of Greek and Latin origin

There are rules for plural forms of words of Greek and Latin origin. For example:

• If the word ends in -us, change it to -i (e.g. stimulus becomes stimuli).
• If the word ends in -a, change it to -ae (e.g. vertebra becomes vertebrae).

Other rules

• In hyphenated words, add -s to the most important word, usually the noun (e.g. sister-in-law becomes sisters-in-law).
• Some words have the same singular and plural form (e.g. deer stays as deer).
• Some plurals alter the vowels in the middle of words (e.g. foot becomes feet).

To help students navigate the complexities of plurals—and their exceptions—here’s a helpful video that explains the different plural rules with clear examples.

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