过去永远存在，现在永远是过去。

引力波的探测为我们打开了一扇观察宇宙的新窗口。

I have come to believe that a great teacher is a great artist and that there are as few as there are any other great artists. Teaching might even be the greatest of the arts since the medium is the human mind and spirit.

Curiosity and perseverance can change the world.

严厉的家庭没有凶悍的奴仆，而慈爱的母亲却会有败家的儿子。