According to the passage, what makes it difficult for researchers to know if an energy drink gives people energy?

FAMILY LIFE IN THE UNITED STATES Family life in the United States is changing. Fifty or sixty years ago, the wife was called a “housewife”. She cleaned, cooked, and cared for the children. The husband earned the money for the family. He was usually out working all day. He came home tired in the evening, so he did not do much housework. And he did not see the children very much, except on weekends. These days, however, more and more women work outside the home. They cannot stay with the children all day. They, too, come home tired in the evening. They do not want to spend the evening cooking dinner and cleaning up. They do not have time to clean the house and do the laundry. So who is going to do the housework now? Who is going to take care of the children? Many families solve the problem of housework by sharing it. In these families, the husband and wife agree to do different jobs around the house, or they take turns doing each job. For example, the husband always cooks dinner and the wife always does the laundry. Or the wife cooks dinner on some nights and the husband cooks dinner on other nights. Then there is the question of the children. In the past, many families got help with child care from grandparents. Now families usually do not live near their relatives. The grandparents are often too far away to help in a regular way. More often, parents have to pay for child care help. The help may be a babysitter or a day-care center. The problem with t his kind of help is the high cost. It is possible only for couples with jobs that pay well. Parents may get another kind of help form the companies they work for. Many companies now let people with children work part-time. That way, parents can spend mo re time with their children. Some husbands may even stop working for a while to stay with the children. For these men there is a new word: they are called “househusbands”. In the USA more and more men are becoming househusbands every year. These changes in the home mean changes in the family. Fathers can learn to understand their children better, and the children can get to know their fathers better. Husbands and wives may also find changes in their marriage. They, too, may have a better understanding of each other.

The word “they” in paragraph 5 refers to .............

The changes in the American home mentioned in this passage may ...............

What is “extreme” weather? Why are people talking about it these days? “Extreme” weather is an unusual weather event such as rainfall, a drought or a heat wave in the wrong place or at the wrong time. In theory, they are very rare. But these days, our TV screens are constantly showing such extreme weather events. Take just three news stories from 2010: 28 centimetres of rain fell on Rio de Janeiro in 24 hours, Nashville, USA, had 33 centimetres of rain in two days and there was record rainfall in Pakistan. The effects of this kind of rainfall are dramatic and lethal. In Rio de Janeiro, landslides followed, burying hundreds of people. In Pakistan, the floods affected 20 million people. Meanwhile, other parts of the world suffer devastating droughts. Australia, Russia and East Africa have been hit in the last ten years. And then there are unexpected heat waves, such as in 2003 in Europe. That summer, 35,000 deaths were said to be heat-related. So, what is happening to our weather? Are these extreme events part of a natural cycle? Or are they caused by human activity and its effects on the Earth’s climate? Peter Miller says it’s probably a mixture of both of these things. On the one hand, the most important influences on weather events are natural cycles in the climate. Two of the most famous weather cycles, El Niño and La Niña, originate in the Pacific Ocean. The heat from the warm ocean rises high into the atmosphere and affects weather all around the world. On the other hand, the temperature of the Earth’s oceans is slowly but steadily going up. And this is a result of human activity. We are producing greenhouse gases that trap heat in the Earth’s atmosphere. This heat warms up the atmosphere, land and oceans. Warmer oceans produce more water vapour – think of heating a pan of water in your kitchen. Turn up the heat, it produces steam more quickly. Satellite data tells us that the water vapour in the atmosphere has gone up by four percent in 25 years. This warm, wet air turns into the rain, storms, hurricanes and typhoons that we are increasingly experiencing. Climate scientist, Michael Oppenheimer, says that we need to face the reality of climate change. And we also need to act now to save lives and money in the future. (Source: 2015 National Geographic Learning.www.ngllife.com/wildweather) 

It is stated in the passage that extreme weather is ..............

Which sentence best expresses the main idea of the second paragraph?

Which statement is NOT supported by the information in the passage?

According to the passage, extreme weather is a problem because ............

Because writing has become so important in our culture, we sometimes think of it as more real than speech. A little thought, however, will show w hy speech is primary and writing secondary to language. Human beings have been writing (as far as we can tell from surviving evidence) for at least 5000 years; but they have been talking for much longer, doubtless ever since there have been human beings. When writing did develop, it was derived from and represented speech, although imperfectly. Even today there are spoken languages that have no written form. Furthermore, we all learn to talk well before we learn to write; any human child who is not severely handicapped physically or mentally will learn to talk: a normal human being cannot be prevented from doing so. On the other hand, it takes a special effort to learn to write. In the past many intelligent and useful members of society did not acquire the skill, and even today many who speak languages with writing systems never learn to read or write, while some who learn the rudiments of those skills do so only imperfectly. To affirm the primacy of speech over writing is not, however, to disparage the latter. One advantage writing has over speech is that it is more permanent and makes possible the records that any civilization must have. Thus, if speaking makes us human, writing makes us civilized. 

We sometimes think of writing as more real than speech because ..............