OG11th-8

原题:  Carnivorous mammals can endure what would otherwise be lethal of body heat because they have a heat-exchange network which kept the brain from getting too hot .

A .  which kept

B.   that keeps

C.   which has kept

D.   that has been keeping

E.   having kept

此题根据时态很容易就能选出答案为B . 可OG的解释牵扯到另外一个知识点,就是引导限制性定语从句只能用that , 也就是说把A  改为  which keeps 也是不对的, 这个规则之前没有碰到过, 所以不敢确定自己的理解是否正确,请大牛指教啊. 谢谢!

我非nn,但我觉得你的理解是对的。

谢谢大家. 

这样的话,是不是可以简单的理解为: 有逗号只能用which ,没有逗号只能用that