theart.那；这；这些；那些adv.（用于比较级前）更加；用于最高级前；(用于形容词、副词比较级前)越 ... 越 ...Thermopuls连续和脉冲超短波电疗机

1. Sweet potato was the staple of their diet.
   过去甘薯是他们的主食。
2. Cereal crops are the main food of our daily life.
   谷类作物是我们日常生活中的主食。