SINGULAR TO PLURAL
Some words have the same spelling in both singular and plural forms.
-   Advice = singular
-   Advice = plural

-   Baggage = singular
-   Baggage = plural
-    Series = singular
-    Series= plural

-    Information
-    Information
-   Sheep = singular
-   Sheep = plural

-   Aircraft = singular
​-   Aircraft = plural
However -  Fish = singular and plural, if the fish are of the same species
                 Fish = fishes if referring to more than one species of fish
To make most words plural, add an 's'.
​
  • Keys
  • Socks
  • Bananas
  • Boats
Add 'es' to words ending in s, x, z, ch, sh - or 'o' when preceded by a consonant.
-   Address = addresses
-   Branch = branches
-   Bus = buses 
​-   Potato = potatoes
-   Beach = beaches
-   Brush = brushes
-   Buzz = buzzes 
​-   Tomato = tomatoes
-   Six = sixes
-   Fox = foxes
​-   Glass = glasses  
Words that end in an 'f' always change the 'f' to a 'v' to become plural:
​
  • Knife = knives
  • Life = lives
  • Half = halves
  • Wife = wives
  • Buck  =  bucks or bucks
  • Boar  =  boar or boars
  • Mackerel = mackerel or mackerels
  • Quail = quail or quails
  • Reindeer = reindeer or reindeers
  • Roe  =  roe or roes
  • Shrimp  =  shrimp or shrimps
  • Trout  =  trout or trouts
  • Whale  =  whale or whales
  • Buffalo  =  buffaloes
  • Echo  =  echoes
  • Mango = mangoes
  • Mosquito = mosquitoes
  • Torpedo = torpedoes
  • Veto = vetoes
  • Volcano = volcanoes
  • City = cities
  • Cherry = cherries
  • Country  =  countries
  • Cry = cries
  • Sky = skies
  • Spy = spies
  • Story - stories
  • Strawberry = strawberries
  • Calf = calves
  • Half = halves
  • Knife = knives
  • Leaf = leaves
  • Life = lives
  • Shelf = shelves
  • Thief = thieves
  • Wolf = wolves
  • Bay = bays
  • Boy = boys
  • Chimney = chimneys
  • Donkey = donkeys
  • Guy = guys
  • Journey = journeys
  • Monkey = monkeys
  • Ray = rays
  • Toy = toys
When 'y' is preceded by a consonant, change the 'y' to an 'i' and add 'es'.
  • Party = parties
  • Story = stories
  • Try = Tries
  • Army = armies
  • Bunny = bunnies
  • Belief = beliefs
  • Bluff = bluffs
  • Chef = chefs
  • Chief = chiefs
  • Giraffe = giraffes
  • Handcuff = handcuffs
  • Reef = reefs
  • Criterion = criteria
  • Dormouse = dormice
  • Foot = feet
  • Goose = geese
  • Louse = lice
  • Man = men
  • Mouse = mice
  • Tooth = teeth
  • ​Woman = women
  • ​Axis = axes
  • Basis = bases
  • Crisis = crises
  • Diagnosis = diagnoses
  • Ellipsis = ellipses   
  • Oasis = oases
  • Parenthesis = parentheses
  • Thesis - theses
  • Brother-in-law = brothers-in-law
  • Go-between = go-betweens
  • Cupful = cupfuls
  • Man-of-war = men-of-war
  • Mix-up = mix-ups
  • Passerby = passersby