简单的道理英语

He doesn't even know such a simple thing.

He doesn't know such a simple reason actually !

he even do not know such simple principle

1、狗和影子(The Dog and the Shadow)It happened that a Dog had got a piece of meat and was carrying it home in his mouth to eat it in peace. Now, on his way home he had to cross a plank lying across a running brook. As he crossed, he looked down and saw his own shadow reflected in the water beneath. Thinking it was another dog with another piece of meat, he made up his mind to have that also. So he made a snap at the shadow in the water, but as he opened his mouth the piece of meat fell out, dropped into the water and was never seen more. 一只狗嘴里衔着一块肉，走过一条河上面的桥，看见他自己在水里的影子，以为是另一只狗，那时狗衔着的肉，比他自己的还要大一倍。因此他仍掉自己的那一块，狠狠地扑向那只狗，想夺到那一块较大的肉。结果两头都落了空，因为他想要抓取在水中的那一块，只不过是一个影子，而原来的那一块，也被水冲走了。Beware lest you lose the substance by grasping at the shadow. 谨记，切莫因追逐幻影而丢失已有的东西。