【释义】一尺长的木头必定会有节疤,一寸大的美玉也难免会有瑕疵。
"The only limit to our realization of tomorrow is our doubts of today."
Education is the foundation of sustainable forestry—people protect what they understand.
行为主义者对人类行为的兴趣不仅仅是旁观者的兴趣——他想要控制人类的反应,就像物理科学家想要控制和操纵其他自然现象一样。