人为某样东西实际支付的成本至少是标价的两倍，因为买来后设置、学习、维护、修理，以及最后处置，也需要耗费精力、时间和钱。不是所有的实际成本都在价签上。实际成本是标价的2倍。
你男朋友那么紧张是因为我。
"The only way to deal with an unfree world is to become so absolutely free that your very existence is an act of rebellion."
Making games requires patience, quality products need time to polish.
"Quantum computing is not just a new way of processing information; it is a new way of thinking about the very nature of computation."
In science, as in life, the important things are rarely simple or obvious.