After years of overwork, my father’s health ____ and he had to retire from business.

Professor Williams keeps telling his students that the future ______to the well-educated.

The cigarette end thrown away by a careless farmer ______ the big fire and caused a great loss to them．

After retirement, she _____ herself in _______the poor children.

—What a beautiful necklace!—Yes.But the necklace I __________ 80 dollars is made of glass.