VOA慢速英语:Defeat Malaria, or Just Control It?; New Polio Vaccine

例句：The animal began to sicken and soon died.
      这只动物患了病很快就死了。
 
2.relatively adv.相对地,比较而言;相当

例句：a piece that is relatively easy to play
      比较容易演奏的乐曲

      A relatively firm material can be anticipated.
      可以提前准备一种较为坚实的材料。

3.largely adv.在很大程度上, 大半地, 主要地

例句：This country is largely desert.
      这个国家大半都是沙漠。

      His success is largely due to his own hard work.
      他的成功主要是靠他自己的努力。

4.normally adv.通常; 正常地

例句：Let's face it, people who have a capacity for work normally succeed.
      不管怎么说, 有工作能力的人一般总会成功的。

5.effectiveness n.有效;有力

例句：Bad diction marred the effectiveness of his speech.
      措词不当影响了他演说的效果。

      The drugs work well at first but gradually lose their effectiveness.
      这些药的效果起初非常好，但后来逐渐失效。