数学直觉就像肌肉一样 - 通过锻炼会变得更强大。
我不敢说自己从未担心害怕过。 实际上我希望少一点担心害怕,因为它让我分心,使我焦虑。
The future of forestry lies in balancing economic growth with ecological responsibility.
Friendship is love without his wings.