【温故知新】 用适当的关系词填空，并体会其用法。 ①Ancient China was a place ______ states were often at war with each other. ②But it was also a time _____ there were many great philosophers. ③Confucius (551BC—479BC) is the philosopher ______ influence has been the greatest. ④Mencius believed that the reason ____ man is different from animals is that man is good.

where

when

whose

why