请教一道比较结构动词补出的题，NN们帮忙解答一下，实在想不明白

keaneice

There is a widespread belief in the United States and Western Europe that young people have a smaller commitment to work and a career than their parents and grandparents and that the source of the change lies in the collapse of the "work ethic."



(A) a smaller commitment to work and a career than their parents and grandparents

(B) less of a commitment to work and a career than their parents and grandparents

(C) a smaller commitment to work and a career than that of their parents and grandparents

(D) less of a commitment to work and a career than their parents and grandparents had

(E) a lessening of the commitment to work and a career that their parents and grandparents had

答案D

不大明白前面young people have 这个have是实意动词，为什么后面补充要补助动词？而不是用did呢？谢谢！

果汁软糖

had是助动词么……应该理解为have的过去式呀

keaneice

had是助动词么……应该理解为have的过去式呀

-- by 会员 果汁软糖 (2009/12/9 23:34:09)

prep上的注释说是助动词，而且过去式的话，也是应该补did吧

jenny1989

想了一下 觉得这是时态不同的缘故
说不出来了。。呃。。

keaneice

想了一下 觉得这是时态不同的缘故
说不出来了。。呃。。

-- by 会员 jenny1989 (2009/12/10 0:29:06)

快去请高人来，哈哈

jenny1989

哈哈 不用NN啦 小J给你解释清楚了
这里其实是less of a commitment to work and a career than their parents and grandparents had （had）第二个had是have的过去时 have是实义动词 补出的had的助动词
由于前后时态不同 所以有点奇怪 后边是过去完成时态 因为父辈的梦想已经在过去结束了 合理体现完成
understand？

keaneice

哈哈 不用NN啦 小J给你解释清楚了
这里其实是less of a commitment to work and a career than their parents and grandparents had （had）第二个had是have的过去时 have是实义动词 补出的had的助动词
由于前后时态不同 所以有点奇怪 后边是过去完成时态 因为父辈的梦想已经在过去结束了 合理体现完成
understand？

-- by 会员 jenny1989 (2009/12/10 0:53:52)

嗯，我也这么想过，不过有一点疑虑，为什么要用过去完成时？？ 直接过去时不好吗？

jenny1989

都可以 含义合理都OK 不用管谁更好 这里没有did的选项啊

jenny1989

钻语法点会钻死的。。更何况时态是最花时间的思考。。

keaneice

呵呵，谢谢Jenny小姑娘