数算练习告诉我们算术运算的原理,而不是单单的记忆和不断演算。
The greatest sweetener of human life is Friendship. To raise this to the highest pitch of enjoyment, is a secret which but few discover.
过去是你记得的、你想象你记得的、你确信你记得的、或者你假装记得的。
二战前生活很简单。之后,我们有了系统。