主语比较？

A study commissioned by the Department of Agriculture showed that if calves exercise and associated with other calves, they will require less medication and gain weight quicker than do those raised in confinement.

(A) associated with other calves, they will require less medication and gain weight quicker than do

(B) associated with other calves, they require less medication and gain weight quicker than

(C) associate with other calves, they required less medication and will gain weight quicker than do

(D) associate with other calves, they have required less medication and will gain weight more quickly than do（E）

(E) associate with other calves, they require less medication and gain weight more quickly than

Choice E, the best answer, uses the adverbial phrase more quickly than to modify the verb phrase gain weight. In A, B, and C, quicker than is incorrect because an adjective should not be used to modify a verb phrase. E is also the only choice with consistent verb tenses. The first verb in the clauses introduced by showed that is exercise. A and B incorrectly compound that present tense verb with a past tense verb, associated. C and D correctly use associate, but C follows with the past tense required and D with the present perfect have required. Both C and D incorrectly conclude with the future tense will gain

想不通为什么不用do在than 后？

记得以前有个比较  I eat apple faster than you do主语比较

                             I eat apple faster than you 宾语比较

如果按这样看的话，E 就有问题了阿，谁帮忙解释下阿, 阿门

up

somebody could help me?

偶滴神阿，来点comments该多好啊。

比较主语，

没有歧义就可以省，省掉是完全正确的，但大部分情况不省，仅仅是为了结构上好看，这是从修辞上追求parrallelism。

另一方面，有歧义就不能省。

如比较宾语

乱加do而改变，合理的比较对象也不行。

这是唯一原则。你看到的说法是误导。。。

这么说是看相互比较的主语（或宾语）是否是同类，以及句意拉

谢谢楼上