光波,无论是以太波还是其他波,在所有情况下都是时间上的周期性过程。
最好的商业模式是垄断。
学校必须代表当下的生活——对孩子来说,这种生活与他在家庭、邻里或操场上所进行的生活一样真实和重要。
Keep your head up, God gives his hardest battles to his strongest soldiers.
I want to do what I like all day. I want to sit in a roadside cafe and look in the shop window. Walk in the rain and do something fun or even exciting.