Bài tập đọc hiểu (Có đáp án) (Đề 2)

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

A large number of inventions require years of arduous research and development before they are perfected. For instance, Thomas Edison had to make more than 1,000 attempts to invent the incandescent light bulb before he finally succeeded. History is replete with numerous other examples of people trying, yet failing to make inventions before they eventually succeeded. Yet some inventions have come about not through hard work but simply by accident.

In most cases, when someone unintentionally invented something, the inventor was attempting to create something else. For example, in the 1930s, chemist Roy Plunkett was attempting to make a new substance that could be used to refrigerate items. He mixed some chemicals together. Then, he put them into a pressurized container and cooled the mixture. By the time his experiment was complete, he had a new invention. It was not a new substance that could be used for refrigeration though. Instead, he had invented Teflon, which is today most commonly used to make nonstick pots and pans. Similarly, decades earlier, John Pemberton was a pharmacist in Atlanta, Georgia. He was attempting to create a tonic that people could use whenever they had headaches. While he was not successful in that endeavor, he managed to invent Coca - Cola, the world - famous carbonated soft drink.

Scientists have also made crucial discoveries by accident when they were conducting experiments. In 1928, Alexander Fleming discovered penicillin, an antibiotic, in this manner. He discovered some mold growing in a dish with some bacteria. He noticed that the bacteria seemed to be avoiding the mold. When he investigated further, he determined some of the many useful properties of penicillin, which has saved millions of lives over the past few decades. Likewise, in 1946, scientist Percy Spencer was conducting an experiment with microwaves. He had a candy bar in his pocket, and he noticed that it suddenly melted. He investigated and learned the reason why that had happened. Soon afterward, he built a device that could utilize microwaves to heat food: the microwave oven.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

In 1752, Benjamin Franklin made his textbook experiment with a brass key and a silk kite that he flew in a thunderstorm to prove that lightning and electricity are the same thing. In 1920, a kite-flying championship for families and individuals was held in London. These two seemingly unrelated events underscore the fact that kites can be flown for both pleasure and scientific purposes. For example, in the 1800s weather bureaus flew kites to record temperature and humidity at certain altitudes. On one occasion, ten kites were strung together and flown at a height of four miles to lift men and carry cameras aloft.

The kite’s ability to fly depends on its construction and the way that its line is attached. The familiar diamond - shaped kite flies when its covered face is aligned against the wind flow. The line attached to the nose of the kite pulls it into the wind, thus creating the necessary angle for the lift force. If the kite’s construction and the angle of the air stream are correct, the kite will encounter greater pressure against its face and lower pressure against its back. The difference in the pressure creates a lift that causes the kite to rise until it hangs level from its bridle. Its angle against the wind should be sufficiently large or small to create maximum lift to overcome both drag and gravity. The towing point to which the line is attached is important because it sets the kite’s angle relative to the air flow. Although the kite must be headed up and into the wind with a velocity of 8 to 20 miles per hour, it can maintain its position through a tail, a rudder, a keel, vents, or tassels.