OG253，大全817和586―――than后面的比较对象可以省略吗？

OG253，大全817和586―――than后面的比较对象可以省略吗？

OG253的正确答案 (B) which was colder and wetter than usual in some regions, slowing

大全817的正确答案(E) previously estimated and that the savings rate was slightly higher

大全586的题目中未划线部分：Prompted by new evidence that the health risk posed by radon gas is far more serious than was previously thought, property owners are being advised by authorities to test all dwellings below the third floor for radon gas and to make repairs as needed.

这三题，比较结构than 后面的比较对象都没有出现，哎哟，别说用代词了，干脆将代词都省了。如果说OG253中的than usual 是idiom话，817和586该怎么解释呢，586中甚至将previously thought 直接作了was的主语，是不是可以认为previously estimated 和previously thought可以代替比较对象呢？请大家帮忙看看，给个解释。谢谢大家！

关于比较问题有好多讨论，到精华贴里找找吧。

在版面右上角，直接点击“精华”。

可以省略... as long as the comparing targets are clear and logical! But, there are many cases in which the 2nd target can't be omitted: see ecsniffer mm's http://forum.chasedream.com/dispbbs.asp?BoardID=23&ID=36523

Please note that "was" can't be omitted because it's needed to introduce a different tense:

Prompted by new evidence that the health risk posed by radon gas is far more serious than was previously thought, property owners are being advised by authorities to test all dwellings below the third floor for radon gas and to make repairs as needed.

多多讨论．．．

感谢兔儿MM，是啊，要多多讨论才行咯。

以下是引用llrllrllr在2005-11-9 19:46:00的发言：


右上角没有找到精华呀,在哪里呀?

是到语法区总版面有上角，并不是本讨论页面的右上角！：）