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

好的研究就像好的故事——有開頭、中間和結尾，邏輯連貫。

I don't think that everyone should become a mathematician, but I do believe that many students don't give mathematics a real chance.

The next green revolution will be led by those who bridge tradition and innovation.

"You have to believe in yourself when no one else does."

I'm the reason your snow won't melt.

預測未來的最好方式就是創造未來。