PrintCompound nouns form their plurals by adding –s to the principal word. Examples are given below:

  • Commander-in-chief (singular), commanders-in-chief (plural)
  • Son-in-law, sons-in-law
  • Daughter-in-law, daughters-in-law
  • Stepson, stepsons
  • Maidservant, maidservants
  • Passer-by, passers-by

Notes

The plural of manservant is menservants and not manservants or menservant.
Spoonful and handful are regarded as one word and their plural forms are spoonfuls and handfuls.

Many nouns which have their origin in foreign languages have kept their original plural forms:

  • Formula (singular), formulae or formulas (plural)
  • Index, indices
  • Radius, radii
  • Memorandum, memoranda
  • Axis, axes
  • Analysis, analyses
  • Criterion, criteria

Letters, figures and other symbols form their plural by adding an apostrophe and –s.
Dot your i’s and cross your t’s.

PrintFriendly

Related posts:

  1. Formation of Plural Nouns
  2. Nouns with Identical Singular and Plural Forms
  3. Nouns with Different Meanings in the Singular and the Plural
  4. Noun: Number
  5. Proper Nouns and Common Nouns
  6. Collective Nouns and Abstract Nouns
  7. Formation of the Feminine Gender