VOA慢速英语:Unwrapping the Genetic Secrets of a Chocolate Bar

例句：It's a rainy day today.
      今天是一个雨天。

      Soon the rainy season sets in.
      很快雨季到了。

2.productive adj.多产的, 富饶的

例句：They lived on the productive land.
      他们生活在富饶的土地上。

富有成效的; 有益的

例句：We had a productive meeting that solved some problems.
      我们开了一个富有成效的会议, 解决了一些问题。

3.contain v. 包含,包括,容纳;遏制,抑制,克制

4.organism n.有机物, 有机体; 生物

例句：It was an infectious organism that he studied.
      他研究的是一种可传染病菌的微生物。

有机体系

例句：The army is an extremely complex organism.
      军队是一个极其复杂的组织。

5.yield n.产量, 收益

例句：All these have helped raise farm yields steadily.
      所有这些都有助于农业产量的稳步提高。

      The yields on his shares have increased in this year.
      今年他的股票红利增加了。