色多多在线观看播放-色多多在线观看高清免费-色多多在线观看视频-色多多在线看-欧美aaaaa性bbbbb小妇-欧美aaaav免费大片

The only way to learn mathematics is to do mathematics.

I don’t let other people define who I am.

技術可以幫助我們管理森林，但它永遠無法取代自然的智慧。

The end of history will be a very sad time. The struggle for recognition, the willingness to risk one's life for a purely abstract goal, the worldwide ideological struggle that called forth daring, courage, imagination, and idealism, will be replaced by economic calculation, the endless solving of technical problems, environmental concerns, and the satisfaction of sophisticated consumer demands.

我們面臨這樣一個進退兩難的境地，即教育已經成為智慧和自由思想最主要的障 礙之一。

成功的關鍵不僅在于制造產品，還在于理解使用它的人。

The Soviet Union was a civilization of fear, where people lived in constant dread of the knock on the door at night.