Page 139 - Webster's Speller

18. When the singular ends in f, the plural is usually formed by changing f into v, with es.
life, lives; wife, wives; beef, beeves; loaf, loaves; leaf, leaves; shelf, shelves; wharf, wharves; calf, calves; half, halves; sheaf, shaves; their, thief, thieves.
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Adjectives formed from nouns the addition of y.
bulk (noun), bulky (adjetive); flesh, fleshy; silk, silky; milk,
milky; pith, pithy, rain, rainy; hill, hilly.
Some nouns when they take y, lose e final.
flake, flaky; plume, plumy; scale, scaly; smoke, smoky; stone, stony; bone, bony.
Adjectives formed from nouns by ly.
friend (noun), friend-ly (adjective); home, home-ly; love, love-ly; time, time-ly; man, man-ly; cost, cost-ly; earth, earth-ly; lord, lord-ly.
Nouns formed from adjectives in y, by changing y into i and taking ness.
hap-py (adjective), hap-pi-ness (noun); loft-y, lof-ti-ness; la- zy, la-zi-ness; emp-ty, emp-ti-ness; drow-sy, drow-si-ness; diz-zy, diz-zi-ness; sha-dy, sha-di-ness; chil-ly, chil-li-ness.
Adverbs formed from adjectives in y, by changing y into i, and the addition of ly.
craft-y (adjective), craft-i-ly (adverb); luck-y, luck-i-ly; loft- y, loft-i-ly; gloom-y, gloom-i-ly.
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