VOA慢速英语:Finding New Ways to Treat Rheumatoid Arthritis

倍数比较。要注意的是，这里的three times more likely to指的是可能性高出三倍。three times as指的是可能性是它的三倍。

2.Instead, the protein builds up in the joints and attacks cartilage and bone.

build up逐步建立, 增进, 增强,使增大

例句：Many a large and big business has been built up from small ones.
      很多大企业都是从小规模发展起来的。

      The clouds are building up.
      云越积越厚。

3.The MedlinePlus Medical Encyclopedia, a United States government website, says there are more than one hundred different kinds.

more than超过,多于

例句：It's no more than one mile to the shops.
      到商业区不过一英里。

在这一句中是最常见的用法，不过也还有其他引申的意思：

很, 非常

例句：I was more than a little angry when I saw how they'd ruined it.
      当我见到他们是怎样把它破坏时, 我不禁大为愤慨。

      She was dressed more than simply.
      她穿着十分朴素。

不只是

例句：His report is more than a survey.
      他的报告不只是一份调查。
 
4.Some autoimmune forms of arthritis, if not treated, may cause joints to become deformed.

if省略形式

if+过去分词的省略形式：

其中的过去分词可视为是被省略的被动结构，即在if与形容词之间省略了主语和助动词be。如：

例句：He will come if asked.= He will come if he is asked.
      他如被邀就会来。

      The medicine is quite effective if taken in time.=The medicine is quite effective if it is taken in time. 这
      药要是能按时服用，效果是很好的。

还有另外一种省略形式：

if + 形容词

这类结构通常可视为在if与形容词之间省略了“主语+动词be的适当形式”。如：

Send the goods now if ready.= Send the goods now if they are ready. 货物如已备好，请即送来。

If true, this will cause us a lot of trouble.= If it is true, this will cause us a lot of trouble. 这事若是事实，它将给我们造成许多麻烦。

注：这类省略结构中有的已构成相对固定的搭配，if necessary (如果需要)，if possible (如果可能)等。如：

If necessary, ring me at home. 如果必要，可往我家里打电话。

If possible, let me know beforehand. 如果可能，可在事前通知我。