[求助]两道题

以下是引用linlin315在2003-10-8 22:01:00的发言：
2002年5月
25、Addressing themes that were unique American, the poet Walt Whitman celebrated the lives of ordinary people.
the key: B实在是想不通，我认为答案应该是D。表示普通人不是要加the的吗？

我认为应该是themes that were unique to American!

39、Due to persistent inbreeding, self-pollinating plants have genetically more uniform than cross-pollinated plants, which harbor more genetic variability.
the key:B单独have应该没错吧？？但是这句话好像是有点问题了，应该是plants have gene more uniform than cross-pollinated plants才对吧？？原来的have genetically more uniform than 该如何解释呢？？

这个应该是have been more uniform than 吧?

兔兔叩谢ing