Поставьте следующие существительные во множественном числе: a lamp,a coach,a slice,a party,a solo,a curriculum,an ox,a sheep,a mouse,a writer,a play, a foot, a theatre,a deer,a box,a trouble,a swine,a life,a part,a handkerchief.

Правильные формы множественного числа:

a lamp — lamps
a coach — coaches
a slice — slices
a party — parties
a solo — solos
a curriculum — curricula / curriculums
an ox — oxen
a sheep — sheep
a mouse — mice
a writer — writers
a play — plays
a foot — feet
a theatre — theatres
a deer — deer
a box — boxes
a trouble — troubles
a swine — swine
a life — lives
a part — parts
a handkerchief — handkerchiefs

Итоговый ряд:

lamps, coaches, slices, parties, solos, curricula/curriculums, oxen, sheep, mice, writers, plays, feet, theatres, deer, boxes, troubles, swine, lives, parts, handkerchiefs.