Children make pumpkins.
Children wear costumes.
Children say trick-or-treating.
Children recive candy.
Children shout "Trick or treat!"
Witches say spells.
Witches transforms people into frogs.
Witches fly on brooms.
Vampires turn into bats.
Vampires suck blood.
Ghosts appear in old houses and castles.
Werewolves howl at the moon.
Я думаю так. Если, конечно, вам не был дан список слов для использования в этом задании.