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

A pure hand needs no glove to cover it.

小說是一種永遠處于危機中、瀕臨消失邊緣的藝術形式，而這正是它保持生命力的原因。

I'm very competitive with myself. I'm always trying to push beyond my own boundaries.

The concept of computational complexity is not just about how fast we can compute, but also about understanding the limits of what can be computed.

數學是所有科學建立的基礎。

地理學是關于地方的科學，而不是關于人的科學。