Adding -s

We add -s to words for two reasons:

  1. to make plural nouns (boy, boys)
  2. to form the 3rd person singular of the present simple tense (I work, you work, he works)

Spelling Rule
Just add -s to the end of the word, for example:

Exceptions
(note: C=consonant)

If the word ends in do this and add Examples
ch
s
sh
x
z
nothing es church, churches
mass, masses
brush, brushes
fax, faxes
box, boxes
chintz, chintzes
f
fe
remove f or fe ves wife, wives
calf, calves

except beliefs, cliffs, chiefs, dwarfs, griefs, gulfs, proofs, roofs
C + y remove y ies spy, spies
baby, babies
Note: words that end in -o normally just add -s, except: buffalo, buffaloes; cargo, cargoes (or cargos); domino, dominoes; echo, echoes; go, goes; grotto, grottoes; halo, haloes; hero, heroes; mango, mangoes; mosquito, mosquitoes; motto, mottoes (or mottos); potato, potatoes; tomato, tomatoes; tornado, tornadoes; torpedo, torpedoes; veto, vetoes; volcano, volcanoes