解释:冬天不洗冰水,并不是吝惜冰;夏天不烤火,也不是舍不得火。而是因为这样做对身体不适宜。
The historian must have a kind of faith that humanity will not and cannot perish.
弄虚作假不能长久,遮掩虚假不能长远。
数学的美在于它既是艺术又是科学。
The only limit to our realization of tomorrow is our doubts of today.