科学中最重要的事情是不要停止提问。
The boundary between inside and outside is not a line, but a gradient.
The novel is the highest example of subtle inter-relatedness that man has discovered.
社会主义不是一个可以由政府或政党建立的现成制度。它是工人阶级自身的产物。
Reinforcement is the central factor in the acquisition of new behavior patterns.
