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 stream of thought flows toward survival."

我真的不在乎別人怎么說我。我知道我是誰。

Innovation is not just about creating new things, but also about improving what already exists.

Own only what you can always carry with you: know languages, know countries, know people. Let your memory be your travel bag.

最好的數(shù)學不僅正確，而且具有啟發(fā)性。