我对这场战争了解的不多，但我知道美国的很多年轻人都参与了这场战争。
The strength of a habit is a function of the number of times it has been reinforced.
The only way to achieve your goals is to work hard and never give up.
If you don't keep creating, you will disappear.
Mathematics is not a careful march down a well-cleared highway, but a journey into a strange wilderness, where the explorers often get lost.