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THE VANISHING INVENTION In 1998, a Valencian professor made an amazing claim. Professor Antonio Cervilla discovered how to use water as a substitute for petrol. The scientist said that you could drive from Bilbao to Valencia on just half a litre of water. His invention uses a molybdenum compound to break down water into hydrogen and oxygen. Unlike other methods, no electricity is required and the reaction happens at atmospheric temperature. This impressive technology is based on the way plant enzymes break down water. The use of molybdenum is the perfect choice because, although rare, it is cheap and found all around the planet. Since the claims were made, nothing more has been heard about this fabulous technology. There is no explanation for the disappearance anywhere on the Internet, apart from a list of similar inventions which have also vanished. An inventor from the Philippines called Daniel Dingel developed a water- fuelled car but was arrested and sentenced to 20 years in prison. If this technology were to become widely available, it would prove disastrous for petrol station owners and would also save the planet from the impending environmental catastrophes.
28. The word “substitute” in the passage is closest in meaning to _________.
A. addition B. alternative C. imitation D. solution
29. Which of the following is NOT true about Cervilla’s invention?
A. It happens at atmospheric temperature. B. It imitates something in nature. C. It requires no electricity. D. It uses enzymes to break down water.
30. The word “it” in the passage refers to _________. A. enzyme B. molybdenum C. petrol D. water
31. The word “vanished” in the passage is opposite in meaning to ________.
A. appeared B. produced C. introduced D. invented
32. It is stated in the passage that water-fuelled cars may contribute to A. save energy
B. save environment C. save money D. save time