hold a pen either with their teeth-thereby creating an artificial smile-or with their lips which would produce a(n)()expression.()A. disappointedB. excitedC. joyfulD. indifferent

When you are calling in a noisy area, you are advised to ________.A. use a more sensitive microphoneB. shout loudly into your microphoneC. go away quietly to continue the phone callD. use your hand to help speak into the phone

I wonder how many years ago ______.( )A. did your father retireB. your father retiredC. has your father retiredD. your father has retired

Who founded Google?A. Larry Page and Sergey Brin.B. Karen May and Larry Page.C. Sergey Brin and Karen May.

I apologize for not ________ my promise.A. being keptB. keepingC. to keep

单选题-Could you give us a speech on management functions some day this week?-_______.A. 记带That's a good idea记带B. No,I already have plansC. I'd love to,but I'm busy this week

Mr. Smith ______ as manager, but nobody could take his place.A. set B. returned C. resigned D. began

He gave up his study in college in________.（ ）A. bundleB. despairC. ash

D If you see a person carelessly throw a cigarette to the ground, what are you likely to think? If you hate people throwing things on the ground, you might think, “That person shouldn’t litter.” If you are a smoker, you might think, “I would sure like a cigarette right now.” Most likely, though, you are not thinking. “That unused cigarette butt could be used to make something amazing!” That is, unless you are a creative scientist. If you are, you may see potential——a possibility——where others simply see trash. That is just what has happened in South Korea . The spirit of invention can hit at the strangest times and in the most unusual places. In South Korea , it happened near a trash can. Kim Gil-Pyo is with the Seoul National University . He says he saw people throwing away cigarette butts, which got him thinking. He began wondering if something useful could be made from them. He and other researchers found a way to convert cigarette butts into materials required for high-performance batteries. Kim Gil-Pyo says they looked closely at used cigarette filters (滤嘴), the parts of cigarettes smokers put into their mouths. Filters are made of a material called “cellulose acetate(醋酸纤维素).” Mr. Kim explains that cellulose acetate can be made into another material: carbon. The pieces of cellulose acetate, known as fibers, are changed through a one-step burning process. After this, they are turned into an energy storage material. But why use carbon? Carbon has many qualities that seem to make it the perfect material. Carbon has a high surface area. It conducts electricity well. It also stays stable, unlikely to change, for a long time. And carbon does not cost a lot. All these qualities make it the most popular material for making super-capacitors (超级电容器). Super-capacitors are good at storing energy. They have high-power mass, or density. They require only a short time for recharging. And they have a long lifecycle. Super-capacitors are used in products such as laptop computers and cell phones. They are also used in industrial energy converters, like wind turbine machines. Combining carbon and super-capacitors seems like a perfect marriage. Kim Gil-Pyo tells the Reuters News Agency that cigarette butts could affect the economy in a huge way. They could prove to be a low-cost source of carbon material. They are so cheap that smokers throw them to the ground. And you don’t get much cheaper than that. (1) 67．What may people think seeing a person throw a cigarette to the ground? A. That all depends. B. He should be blamed.C. It causes them to smoke. D. The butts can be reused. (2) 68．Filters can be made into a material that __________. A. is used as the battery surface B. can be turned into electricityC. is very easy and costs nothing D. can hold electricity energy well (3) 69．Super-capacitors made from carbon __________. A. need quite a long time to recharge B. are comparatively very expensiveC. can easily carry an electrical current D. can save a large quantity of electricity (4) 70．The story tells the readers the truth that __________. A. where there is a will, there is a wayB. the most useless is usually the most usefulC. ideas usually hit at the most unusual placesD. one person’s trash is another person’s treasure

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