大全637我这样的理解对吗？请教！

saharaa

637.Several studies have found that the coronary patients who exercise most actively have half or less than half the chance of dying of a heart attack as those who are sedentary.
(A) have half or less than half the chance of dying of a heart attack as those who are sedentary
(B) have half the chance, or less, of dying of a heart attack than those who are sedentary do
(C) have half the chance that they will die of a heart attack, or less, than those who are sedentary do
(D) are at least fifty percent less likely to die of a heart attack as those who are sedentary
(E) are at least fifty percent less likely than those who are sedentary to die of a heart attack

这题答案是E 而E得比较是主谓结构的比较，即谁比谁更有可能得病。但一般主谓结构的比较than后都必须补出助动词。而这里没有补出？！
我的理解是：因为这里是个主系表结构，即没有宾语，所以不会造成than 的代词指代歧义，所以不用补出助动词。
请教大牛，我这样的理解是正确的吗？

sumerlaws

没看明白楼主怎么分析的，
自己做了一下。首先，后面那个who are sedentary，证明这里必须用are。选D 或E
接着就是less likely to 还是less likely than，显然是必须有than。因此我选E

saharaa

此are非彼are ，我觉得，句子结构应该是：
patients （who exercise most actively） are at least fiftypercent less likely than those （who are sedentary） to die of a heart attack

所以我认为两者没有必然联系