You can always juice sales by going down-market, but it's hard to go back upmarket.
Definitions belong to the definers, not the defined.
A book can be a friend, a teacher, and a doorway to another world.
感觉就是秘密。
战争是危险的领域，因此勇气是战士的首要品质。
Internationalization is not a choice but an inevitability; we must have a global perspective.