VOA慢速英语:Scientists Seeking Better Treatments for Multiple Sclerosis

例句：This is a progressive course in English study.
      这是英语学习的渐进课程。

      It was a progressive disease and he would suffer more and more.
      病情逐渐加剧, 他将忍受越来越大的痛苦。

2.spinal a.针的,尖刺的,尖刺状突起的,脊骨的

例句：The vertebrate spine or spinal column.
      脊骨脊椎动物的脊椎或脊柱

3.unconnected adj. 不连接的

例句：Consisting of unconnected distinct parts.
      不连续的由互不关联的部分构成的

4.harden vt.vi.(使)变硬; (使)坚固; (使)硬化

例句：The snow hardened until ice was formed.
      雪成冰后变硬了。

5.environmental adj.(个人)环境的;由个人环境产生的

例句：a comparative study of the environmental costs of different energy sources
      有关使用不同能源的环境代价的对比研究

6.misunderstand vt.误会, 误解

例句：I misunderstood her meaning.
      我误解了她的意思。

      Don't misunderstand what I'm trying to say.
      别误解我要说的话。

7.symptom n.

1.症状
例句：The doctor told her to watch out for symptoms of measles.
      医生叫她注意麻疹出现的症状。

2.征兆
例句：The symptoms manifested themselves ten days later.
      十天后征兆显露出来了。