Singular and Plural Nouns

Twelve nouns ending in f or fe drop the f or fe and add ves. These nouns are calf. half, knife, leaf. life, loaf, self. sheaf, shelf, thief, wife, wolf:

e.g. loaf, loaves wife, wives wolf. wolves etc.

The nouns hoof, scar/and wharf take either s or ves in the plural:

hoofs or hooves, scarfs or scarves, wharfs or wharves

Other words ending in f or fe add s in the ordinary way:

Cliff: cliffs, handkerchief: handkerchiefs, safe: safes