Образуйте множественное число следующих существительных. 1) radio, lesson, court, thief, potato, house, eye, fish, tooth-brush, rose, story, truth,... - вопрос №1399845

Здравствуйте, Елена!

1) a radio --> radios
a lesson --> lessons
a court --> courts
a thief --> thieves
a potato --> potatoes
a house — houses
an eye --> eyes
a fish --> fishes (когда речь идет о различных видах рыб, тогда возможно образование формы множественного числа)
a tooth-brush --> tooth-brushes
a rose --> roses
a story --> stories
the truth --> truths
a key --> keys
a mouse --> mice

2) a child --> children
a path --> paths
a hero --> heroes
a day--> days
a book-case --> book-cases
an oak --> oaks
manner --> manners
a louse --> lice
study --> studies
a goose --> geese
a wolf --> wolves
a yard --> yards
a brush --> brushes
a sofa --> sofas

3) a man --> men
a horse --> horses
an idea --> ideas
a kilo --> kilos
a tooth --> teeth
a brother --> brothers
a cousin --> cousins
a glass --> glasses
a daisy --> daisies
an ox --> oxen
a swine --> swine 
grass --> grass
a lion --> lions
a writing-table --> writing-tables

4) a son-in-law --> sons-in-law
youth --> youths  
a piano --> pianos
a half --> halves
a dream --> dreams
a foot --> feet
a deer --> deer
a child --> children
a material --> materials
mouse --> mice
a servant --> servants
a potato --> potatoes
a cow-boy --> cow-boys

5) a woman --> women
a hoof --> hoofs / hooves
a branch --> branches
a mosquito --> mosquitoes
an ox --> oxen
a frog --> frogs
a mouth --> mouths
a hill --> hills
a root --> roots
a photo --> photos
a foot --> feet
a country --> countries
a joint --> joints
a noun --> nouns