沒(méi)人說(shuō)過(guò)這很容易。
Nobody said it was easy.
數(shù)學(xué)的力量來(lái)自于它的抽象和概括能力，將具體問(wèn)題轉(zhuǎn)化為普遍真理。
The beauty of a woman with passing years only grows!
Prove yourself with effort, not words.