免费的疫苗比昂贵的治疗更有价值，但更难推广。
Free vaccines are more valuable than expensive treatments, yet harder to promote.
文本是从无数文化中心引用的语录组成的。
The only limit to our realization of tomorrow is our doubts of today.
Don't let the noise of others' opinions drown out your own inner voice.
我唯一能依靠的是自己的感知，而它总是在变化。