When there is a prefix, we do not normally add or take away more letters:

There are rules for the plurals of regular nouns and the -s forms of regular verbs.

The general rule is add -s:

If the ending is pronounced as ‘ch’ /tʃ/ or ‘s’ /s/, we add -es /ɪz/:

If a word ends in an -e, we add an -s:

If the word ends in a consonant plus -y, we change -y to i and add -es:

We add -es to some words ending in -o:

However, some words ending in -o only require -s: videos, discos, pianos, memos, photos.

For some nouns ending in -f or -fe, we form the plural by changing the -f or -fe to -ves:

loaf → loaves shelf → shelves thief → thieves wife → wives

We often double the final consonant of a word (b, d, g, l, m, n, p, r, t) when a suffix beginning with a vowel is added (-ed, -er, -est, -ing):

When we add a suffix to a word with more than one syllable, we double the consonant only when the word ends in a stressed syllable (the stressed syllable of the base form is in bold):

Compare, however, visit or enter where the spoken stress is on the first syllable:

Note too that in each case the vowel before the last consonant is a short vowel.

If in doubt about ie or ei, when the sound of the vowel is as in brief /i:/, we spell it ie; but after the letter c, we spell it ei:

Words in which -y has changed to i end in -ies even after a c:

emergency → emergencies

bureaucracy → bureaucracies

We use a final silent -e to indicate that the stressed vowel is long:

Here are some common differences between British and American English spelling. A good learner’s dictionary will give information about other spelling differences: