语法填空（每空至多三个词）

    Mr. Johnson lived in the woods with his wife and children. He owned____ farm, which looked almost abandoned. ____ (lucky), he also had a cow which produced milk every day. He sold or exchanged some of the milk in the towns nearly____ other food and made cheese and butter for the family with what____ (leave). The cow was their only means of support, in fact. One day, the cow was eating grass____ it began to rain heavily. While making great efforts to run away, she____ (fall) over the hill and died. Then the Johnson tried to make a living____ the cow. In order to support his family, Mr. Johnson began to plant herbs and vegetables. Since the plants took a while to grow, he started cutting down trees____  (sell) the wood. Thinking about his children's clothes, he started growing cotton too. When harvest came around, he was already selling herbs, vegetables and cotton in the market____ people from the town met regularly. Now it occurred to____ that his farm had much potential and that the death of the cow was a bit of luck.