PREP-2-83，以前好像没有问过，谢谢

83.      (28949-!-item-!-188;#058&004110)

The number of plant and animal species that humans are known to have forced to extinction in the last half millennium is over 800.

(A) humans are known to have forced to extinction

(B) humans are known as having forced to become extinct

(C) humans are known for forcing to become extinct

(D) are known that humans forced to become extinct

(E) are known as having been forced to extinction by humans

以前好像有人提过，但没有解答。答案是A。但我感觉A中的extinction的用法很怪，不是变成了do to sth.的结构？是不是应该加become extinct更合理些呢？

请大家帮着分析一下，谢谢。

这个是定语从句，你应该这样理解：

humans are known to have forced plant and animal species to extinction
    

所以是force sth to...

谢谢MM的解释，完全明白了。以前是我对to的用法理解有问题，以为不能直接连接名词...基本常识错误，呵呵。