合同标的是双方当事人的权利义务共同所指的对象,一般包括______。
A. 建筑物
B. 工程量
C. 劳务行为
D. 建设资金
E. 工资表
What should be done if one wants to gain or lose weight The process of gaining or losing weight can be explained by comparing your body to your car. Both run 1 fuel, food for your body and gasoline for your car. Both 2 that fuel, first into heat, then energy, some of 3 is used to do work, and some emitted as waste. And 4 your car uses more energy when the engine is racing than when it is idling, 5 does your body use more energy when you are working hard than 6 you are resting. For the purpose of this comparison, 7 , there is one significant difference between them. Your car cannot store fuel by turning it into 8 else; all gasoline not 9 remains as gasoline. But your body stores 10 energy as fat. When the gas tank is 11 empty, the car won’t run; but your body can burn fat to provide more energy. Therefore, if you want to gain weight, you must do 12 of two things: eat more calories (units of heat, therefore energy), or use less through 13 . If you want to lose weight, you do the 14 , decrease your intake of calories or increase the amount of energy you spend. There is 15 way. Gaining or losing weight is always a relation between intake and output of potential energy.
A. reverse
B. relevant
C. different
D. same
What should be done if one wants to gain or lose weight The process of gaining or losing weight can be explained by comparing your body to your car. Both run 1 fuel, food for your body and gasoline for your car. Both 2 that fuel, first into heat, then energy, some of 3 is used to do work, and some emitted as waste. And 4 your car uses more energy when the engine is racing than when it is idling, 5 does your body use more energy when you are working hard than 6 you are resting. For the purpose of this comparison, 7 , there is one significant difference between them. Your car cannot store fuel by turning it into 8 else; all gasoline not 9 remains as gasoline. But your body stores 10 energy as fat. When the gas tank is 11 empty, the car won’t run; but your body can burn fat to provide more energy. Therefore, if you want to gain weight, you must do 12 of two things: eat more calories (units of heat, therefore energy), or use less through 13 . If you want to lose weight, you do the 14 , decrease your intake of calories or increase the amount of energy you spend. There is 15 way. Gaining or losing weight is always a relation between intake and output of potential energy.
A. whereas
B. although
C. just because
D. just as
Continue to Protect or Destroy Ecosystem Biosphere Ⅱ was a spectacular failure. The gleaming glass-and-concrete habitat sprawling across the desert in Oracle, Arizona, was supposed to support eight human "biospherians" for two years. But the seal has to he broken before the experiment ended in 1993. Oxygen had fallen to levels normally seen at an elevation of 17,500 feet. Nitrous oxide had risen to the point where it threatened to cause brain damage. The fresh water supply became contaminated, and vines smothered (厚厚地覆盖) food plants. Insect pollinators (传授花粉的生物) and many other species became extinct. By the end, Biosphere Ⅱ was overrun with swarms of ants and cockroaches. Scientists who gathered recently to review the Biosphere Ⅱ experiment reached a disturbing conclusion: "No one yet knows how to engineer systems that provide humans with the life-supporting services that natural ecosystems produce for free." The problem is that these ecosystems are undergoing wrenching changes. Water and air quality, while improving in some regions, are deteriorating in many others. Carbon dioxide levels in the atmosphere arc climbing. The world’s population could reach 10 billion by 2050. And famed Harvard biologist Edward O. Wilson says the current rate of species losses puts us "in the midst of one of the great extinction spasms (突然进发) of geological history." All of which makes many ecologists wonder whether humans too will soon become extinct. It’s an incredibly important but incredibly difficult question. If we continue on this course, we’re heading for a world in which we will have to engineer services we’ve always received for free from nature. That’s why the failure of Biosphere Ⅱ was so disturbing: it proves that we don’t yet know how to do that. The Biosphere Ⅱ experience demonstrated that maintaining human life is a tricky proposition-especially if we can no longer rely on the services provided by natural ecosystems. If we are currently living through a mass extinction, as Wilson believes, we should consider the past. In the great Permian extinction 245 million years ago, 96 percent of species perished. Eventually, the Earth was repopulated with a rich collection of new species, but it took 100 million years. "That should give pause to anyone who believes that what Homo sapiens (现代人) destroys, nature will redeem," Wilson says. "Maybe so, but not within any length of time that has meaning for contemporary humanity." Edward O. Wilson believes that the mass extinction happened in the past ______.
A. is good news for humans
B. is bad news for humans
C. promoted the development of humans
D. blocked the development of humans