Here are some presumably rock-solid -ves plurals:
calf - calves,
elf - elves,
half - halves,
knife - knives,
leaf - leaves,
life - lives,
loaf - loaves,
self - selves (ourselves, yourselves, themselves),
sheaf - sheaves,
shelf - shelves,
thief - thieves,
wolf - wolves,
wife - wives
But I've seen 'wifes' and 'knifes' (the latter presumably sponsored by confusion with the verb form). Any
Game of Thrones-fan who uses 'direwolfs' should be eaten by one.
Other -ves plurals are less solid:
dwarf - dwarves,
roof - rooves,
hoof - hooves,
scarf - scarves,
wharf - wharves
Straight -s plurals for these are very common and even predominant in some cases, e.g., to my slight horror, 'roofs' is almost orthodox in 2017.
We should admit that English is wildly inconsistent about this kind of end-formation. Many important -f words reserve their -ves end-formation for a widely used verb, especially (apparently) where serious ambiguity would result if the -ves form were also used for a plural:
belief - believes,
grief - grieves,
relief - relieves
But 'leaves' is a
very prominent (homophonic) verbal-form for the plural of 'leaf'!
In sum, both polysemy and orthographic irregularity are so extreme in English that the language is a barely functional contraption. Nobody can spell it, and almost nobody can use it verbally for any extended period without errors. The 'Burn It Down!' impulse of 20C Esperantists made a lot of sense.
