PLURALISING COMPOUND NOUNS

 PLURALISATION OF COMPOUND NOUNS: WHERE DOES THE 'S' GO?

Have you ever wondered whether to write mother-in-laws or mothers-in-law?

What about passerbys or passers-by?

And is it woman pilots or women pilots?

The pluralisation of compound nouns can be tricky, but understanding the rules makes it easier.

Let's learn!

First, what are compound nouns?

A compound noun is a noun formed by combining two or more words to create a single meaning.

Examples:

Toothbrush

Swimming pool

Mother-in-law

Passer-by

Woman pilot

Compound nouns are generally written in three forms:

1. CLOSED COMPOUND NOUNS

These are written as one word, without spaces or hyphens.

Rule: Generally, add -s or -es to the end of the word.

Examples:

Toothbrush → Toothbrushes

Classroom → Classrooms

Bedroom → Bedrooms

Football → Footballs

Haircut → Haircuts

Some have irregular plural forms:

Policeman → Policemen

Fireman → Firemen

2. OPEN COMPOUND NOUNS

These are written as separate words without a hyphen.

Rule: Usually, pluralise the main noun (headword).

Examples:

Swimming pool → Swimming pools

Dining room → Dining rooms

Post office → Post offices

Washing machine → Washing machines

Police officer → Police officers

3. HYPHENATED COMPOUND NOUNS

These are joined using a hyphen.

Rule: Usually, pluralise the main noun, wherever it appears in the compound.

Examples:

Mother-in-law → Mothers-in-law

Father-in-law → Fathers-in-law

Brother-in-law → Brothers-in-law

Sister-in-law → Sisters-in-law

Passer-by → Passers-by

Runner-up → Runners-up

Editor-in-chief → Editors-in-chief

Commander-in-chief → Commanders-in-chief

However, some hyphenated compounds take the plural marker at the end:

Grown-up → Grown-ups

Forget-me-not → Forget-me-nots

4. COMPOUND NOUNS INVOLVING MAN AND WOMAN

This is another important aspect of pluralising compound nouns.

When man or woman forms part of a compound noun referring to a person's occupation or role, both words generally change to their plural forms.

Examples:

Woman pilot → Women pilots

Woman doctor → Women doctors

Woman teacher → Women teachers

Woman driver → Women drivers

Man servant → Men servants

Man nurse → Men nurses

Notice the changes:

One woman pilot → Two women pilots.

One man servant → Several men servants.

IMPORTANT: The plural forms are women and men, not womans and mans.

Also, remember that women pilots and men nurses are open compound nouns. The first word changes to its irregular plural form, while the second noun takes the regular plural marker.

LET'S TEST YOUR KNOWLEDGE!

Choose the correctly pluralised form in each sentence.

1. The two women introduced their _____ to us.

A. mother-in-laws

B. mothers-in-law

C. mothers-in-laws

2. The airline recently employed five _____.

A. woman pilots

B. women pilot

C. women pilots

3. Three _____ were selected for the final round.

A. runner-ups

B. runners-up

C. runners-ups