Number-Singular And Plural

Rule-1
1] By adding –‘s’ to the singular noun.
For ex: girl-girls, toy-toys, student-students, tree- trees.

Rule-2
If noun ends in –y preceded by a consonant , plurals will be farmed by changing – y into ‘i’

Rule-3
If noun ends with –s,-sh,-ch or x, plural will be formed by adding –es to the singular noun.

For Ex.
1. Match – Matches
2. Dish – Dishes
3. Watch – Watches
4. Catch – Catches
5. Tax – Taxes

Rule-4
If the noun ends with –f or –fe, plural will be formed by adding ‘-’ves:
For Ex. 1. Leaf- leaves 2. Thief-thieves

For Ex.
1. Self – Selves
2. Leaf – Leaves
3. Wolf – Wolves
4. Calf – Calves
5. Wife – Wives

Some exceptions for this rule:
1. Dwarf – Dwarfs/ dwarves
2. Hoot – Hoofs/hooves
3. Scarf – Scarfs / scarves
4. Gulf – Gulfs
5. Cliff – Cliffs
6. Handkerchief – Handkerchiefs
7. Proof – Proofs

Rule -5
Following are some singular nouns which are changed into plural by changing the inside vowel.

For Ex.
1. Woman – Women
2. Man – Men
3. Foot – Feet
4. Tooth – Teeth
5. Goose – Geese
6. Mouse – Mice

Rule-6
By changing the noun ending ‘O’ into ‘oes’

For Ex.
1. Mango – mangoes
2. Hero – heroes
3. Volcano – volcanoes
4. Potato – potatoes

Exceptions:
1. Kilo – kilos
2. Logo – Logos
3. Ratio – Ratios
4. Solo – Solos
5. Photo – Photos

Rule-6
Kindly note, following nouns have the singular and the plural alike.

Singular : Plural
1. Swine : Swine
2. Deer : Deer
3. Fish : Fish
4. Series : Series
5. Sheep : Sheep

Note: The plural of fish is referred as fish as well as fishes but formally use fish only.

Rule-7
Following nouns are used only in plurals.
Spectacles, trousers, jeans, shorts, thanks, scissors, bellows

Very important:
Following nouns seem to be plural but are used as singular.
Billiards, measles, mathematics, news, rickets etc.

More examples:
Singular           Plural
–                          (Cattle)
–                          (Poultry)
–                          (People)
–                          (Alms)
–                          (Riches)
(Radius)    –    (Raddi)
(Index)       –   (Indices)
(Terminus)  – (Termini)
(Formula)    – (Formulae
(Crisis)        –   (Crises)
(Son-in-law) – (Sons-in –law)
(Step-son)  –   (Step-sons)
(Passer by) –  (Passers by)
(Man servant) – (Men servant)
(Maid servant) – (Maid servants)
(Criterion) –  (Criteria)
(Index) –  (Indices)