永远不要让年龄成为学习或发现的障碍。
只有理解,才能关心;只有关心,才会帮助;只有帮助,一切才能得救。
The best fertilizer is the farmer's shadow—nothing replaces presence and attention in the fields.
通常,我们只看见我们正在寻找的东西,有时甚至凭空就能看见。
Free vaccines are more valuable than expensive treatments, yet harder to promote.