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

Success comes when you believe in yourself and never give up on your dreams.

"Your time is limited, don't waste it living someone else's life."

最好的數學不僅僅是邏輯的；它是直觀和創造性的，將嚴謹與想象力結合在一起。

"The world is a book, and those who do not travel read only one page."

證明是一種用于使他人相信數學陳述為真的工具。