历史不会长期将自由的维护托付给软弱或胆怯的人。
The only way to save a rhinoceros is to save the environment in which it lives, because there's a mutual dependency between it and millions of other species of both animals and plants.
I’m a very positive thinker, and I think that is what helps me the most in difficult moments.
今天的挑战就是明天的机遇——前提是我们以正确的心态面对它们。
现在很清楚,杂种形成的种子具有两个分化性状中的一个或另一个,其中一半再次发育成杂种形式,而另一半产生保持恒定并以相等数量接收显性或隐性性状的植物。