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

歷史學家的首要職責是如實講述他所見的真相，無論這會取悅還是觸怒何人。

Natural gas is a versatile fuel that can support renewable energy growth by providing reliability when the sun isn't shining and the wind isn't blowing.

The world of the happy is quite another than that of the unhappy.

沒有矛盾的人生不值得書寫。

Banks are special because they create money, and that's why they need special regulation.

腳踏實地，同時不斷追求星辰。

在追求數學真理的過程中，我們常常發現更多的問題而非答案。