热机的动力与实现它的工质无关;其量仅由最终实现热量转移的物体之间的温度决定。
文化的本质在于其连续性和适应性。
If you wish to succeed, you should use perdistence as your good friend, experiece as your reference, prudence as your brother and hope as your sentry.
Combinatorics is the art of counting without counting.