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In the United States, the burning of fossil fuels to make electricity is the largest source of heat-trapping pollution, ____ about two billion tons of CO2 every year.

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Malia’s wedding ring is enormous. It _____ have cost a fortune.

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Jim has a ________ of teaching experience

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The project work in this semester is optional, so students ____ do it

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Never ____ more people ____ in charity work than now

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It is true that digital manufacturing does cut out the middle-man. More and more routine, repetitive assembly tasks will be taken (25) _____ by machines. But as certain jobs disappear, new ones open up in other parts of the factory. Germany in many ways exemplifies this trend. Today, German manufacturers (26) _____ three times more robots than U.S. companies, but they also still employ more humans. Relative to the size of our economies, German's manufacturing workforce is twice the size of America's. From its very beginning, the fourth Industrial revolution has never presented manufacturers with an either-or choice - robots or humans. It has always been about combining the talents of (27) _____ . (28) _____, it is the convergence of artificial and human intelligence that will enable manufacturers to achieve a new era of speed, flexibility, efficiency and connectivity in the 21st century. Machines have the ability to assemble things faster than any human ever could, but humans possess the analytics, domain expertise and valuable knowledge (29) _____ to solve problems and optimize factory floor production

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If it ........................... too much, I will buy the smaller one

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Sue does not help her parents with the housework. She is so irresponsible

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They started ......... a couple of months ago, and now they are inseparable

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The librarian pointed ___________ the sign that said to keep quiet

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Falsely arrested and charged, in a strange country and all alone, Mark was truly at his _______’ end

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When I grow ___________, I want to be an astronaut

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This film is so interesting that my father  …………………it 5 times

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___________ the book, I wrote down some notes.

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The invention of the mobile phone has undoubtedly revolutionized the way people communicate and influenced every aspect of our lives. The issue is whether this technological innovation has (25) _____ more harm than good. In order to answer the question, we must first turn to the types of consumers. Presumably, most parents (26) _____ are always worrying about their children’s safety buy mobile phones for them to track their whereabouts. We can also assume that most teenagers want mobile phones to avoid missing out on social contact. In this context, the advantages are clear. (27) _____, we cannot deny the fact that text messages have been used by bullies to intimidate fellow students. There is also (28) _____ evidence that texting has affected literacy skills. The widespread use of mobile phone has, out of question, affected adult consumers too. What employee, on the way home from work, would be reluctant to answer a call from their boss? Apparently, only 18% of us, according to a survey, are willing to switch off our mobile phones once we've left the office. Admittedly, mobile phones can be intrusive but there are obvious benefits to possessing one. Personally speaking, they are invaluable when it comes to making social or business arrangements at short (29) _____. They also provide their owners with a sense of security in emergency situations

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The young man would always ..........  if there were any girls

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Never ________ to such a fantastic restaurant

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Americans believe that the 50 states make ____________ a union that is greater than the sum of its parts

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I can’t stand him. He always talks as though he______everything

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Oh, we're going ___________ our weekend plans—I refuse to let a little rain stop us!

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He is very skillful at ____ animal noises