do not find the idea of leisure­only life appealing.可知，Vardi教授并不觉得只有休闲的生活吸引人。]

　　4．What will humans face in the next few decades?

　　A．Labor shortage.

　　B．Production surplus.

　　C．Fierce competition.

　　D．Lack of life purposes.

　　D　[细节理解题。由倒数第三段的Humanity is about to face perhaps its greatest challenge ever，which is finding meaning in life.以及最后一段中的If machines can do all the work or even 50 percent of the jobs that we used to do，what will people do？可知，如果机器能够做所有的工作，抑或甚至百分之五十的工作，人类即将面临最大的挑战，那就是找到生活的意义。]

　　B

　　Science fiction writers create imaginary worlds.The way things work in your imaginary worlds will be based on actual science.So it's important for you to be familiar with the scientific principles and inventions that are related to your creation.For example，if you're writing about human living on a planet with zero gravity，then you need to know the effects of zero gravity on the human body.

　　Then you have to figure out the exact rules of your imaginary worlds.And you have to follow them.If humans are able to breathe underwater in Chapter 1，your character can't drown in a swimming pool in Chapter 3.The issue here is maintaining your readers' trust.That means the reader is willing to pretend along with you.If you start out with an ordinary detective novel and then throw in someone breathing underwater in the 6th chapter，you will pull the readers out of their imagination.The same thing happens if you change the rules halfway.

Part of your preparation work for the novel is to map out its worlds in great detail.You should decide the following issues：the history of the world，the geography，what possibilities it offers，how everything works in this new reality，and how all of