I have always considered that the true test of a machine is its practical utility in the hands of the common laborer.
一本儿童书是他们参观的第一个艺术画廊。
The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.
解释:每种药材的生长都有其特定的环境和条件,说明药材产地与品质的关系。
Human freedom is bounded by its choices.