过去是一位老师，如果我们愿意学习的话。

In the world of mathematics, imagination is more important than knowledge.

女性在职业中的选择往往受到社会期望和制度性障碍的限制。

Change is the essence of life. Be willing to surrender what you are for what you could become.

苏联是一个恐惧的文明，人们生活在持续的对夜间敲门声的恐惧中。