Read the following article and select the best answer. Article: What's your earliest childhood memory? Can you remember the first time you heard thunder or watched a television program? Adults seldom recall events much earlier than the year or so before entering school, just as children younger than three or four rarely keep any memory of specific, personal experiences. A variety of explanations have been put forward by psychologists for this "childhood amnesia" . One argues that the _ , the region of the brain which is responsible for forming memories, does not mature until about the age of two. But the most popular theory thinks that, since adults do not think like children, they cannot access childhood memories. Adults think in words, and their life memories are like stories. But when they search through their mental files for early childhood memories to add to this verbal life story, they don't find any that fit the pattern. It's like _ . Now psychologist Annette Simms offers a new explanation for "childhood amnesia". She argues that there simply aren't any early childhood memories to recall. According to Dr. Simms , children need to learn to use someone else's spoken description of their personal experiences in order to turn their own short-term, quickly forgotten impressions of these experiences into long-term memories. In other words, children hear others talk about their experiences--Mother talking about the afternoon spent looking for crabs at the beach or Dad asking them about their day at Ocean Park. Without the help of this kind of verbal description, says Dr. Simms, children cannot form long-term memories of their personal experiences. Question: According to the passage, it is widely believed that _ . - it is impossible for an adult to recall his experiences - adults and children have different brain structures - adults think in words while children think in pictures - adults actually have no access to their childhood memories
adults actually have no access to their childhood memories

Read the following article and select the best answer. Article: The deserts of the world are not all covered with sand. Many of them have surfaces of rock or clay or small stones. They are not flat, either. They often have high hills and deep valleys. There is some plants' life in many parts of the desert. There is little rain in the desert, but it does fall often enough for most plants. The deserts of the world are not uninhabited (not lived by people). People also live outside oases , but these people are not farmers. They have camels, goats, donkeys, sheep, etc. These animals can live on the desert plants and do not need much water. The people of the desert have to move constantly from place to place, they must always look for grass or desert plants for their animals. They usually live in tents. When there is no more food for their animals, they fold up their tents, pat them on their camels and donkeys, and move to another place. In good years, when there is enough food for their animals, they trade their skins and their goats and camel hairs with the people of oases for wheat and fruit. But in bad years, when there is not enough food for their animals, the people of the desert would attack the oases people. But they are also _ , no man in the desert would ever refuse to give a stranger food and water. Question: In the desert _ . - it rains in spring only - it rains for a short time every month - there is some rain, but far from enough - the rainfall is just enough for the plants
there is some rain, but far from enough

Q: Read the following article and select the best answer. Article: Earthquakes and volcanic eruptions usually cause the largest, most disastrous debris ( ) flows. A great many victims of the earthquake that struck Wenchuan of Sichuan province last May were killed not by the quake itself but by the sudden large amounts of debris that followed. Most debris flows occur where the soil is composed mainly of sand or colluviums ( ) . Loose soils made up of bits of sand or colluviums fall apart easily and are main material for fast -moving debris flows. Scientists have conducted endless experiments to find out how debris flows work. They have learned that the amount and the timing of water entering the soil are crucial ( ). Typically, that means debris flows often occur when a long rainy period of many weeks is followed by an intense, brief heavy rain. . More often than not, however, debris flows are started by water, in the form of rain, snow, or river flow. In 1998, heavy rains from Hurricane Mitch unleashed about one million tons of mudslides, burying thousands of people, in Central America. Water flows through the soil until it hits a hard layer of bedrock or clay. There the water builds up, filling the tiny spaces between the soil and rock. That buildup reduces the natural friction ( ) that keeps the rock and soil debris lying on the slope. If conditions are approaching dangerous levels, the slope will then fall down. Despite what scientist know about the fact, debris flows are still impossible to predict at present because there are many other uncertains affect the stability of each slope. However, one thing is known: On hillsides where one debris flow has occurred, another will eventually follow. The next debris flow could take days, weeks, or years to happen. Question: The passage is mainly about _ . - when and where debris flows occur - the experiments that scientists conduct - the causes of debris flows - the possible ways to predict landslides
A: the causes of debris flows

Read the following article and select the best answer. Article: As the capital of China's Shaanxi Province, Xi'an's long history was properly summed up by our English-speaking guide: "If Xi'an is the grandmother of cities, Beijing is a youth and Shanghai is just a baby in the womb. " However, it was not until 1974, following the chance discovery of the Army of Terracotta Warriors by well-digging farmers, that Xi'an was once again pushed onto the international map. Three decades later, the local government is pouring funds into the tourism sector. Ancient monuments and museums are being restored, and various copies of Buddhist and Tang heritage are being constructed to help Chinese tourists rediscover their national heritage. One of those ancient monuments is the Big Wild Goose Pagoda-Xi'an's most sacred monument-which was built in 652 by the monk Xuanzang ,who travelled across India for 18 years and returned with a precious collection of Buddhist sacred texts. In 1966,the Red Guards burnt the pagoda's scriptures, silk wall hangings and other relics in a bonfire that raged all night. But that destruction has largely been forgotten as tourists flock to the newly restored pagoda. The only original remainders-the empty shell of the seven-storey pagoda-light up at night, standing out in the city's skyline. Xi'an is also displaying the glories of the ancient Tang Dynasty, with a 165-acre Tang Paradise Theme Park that is visited by flocks of tourist groups. Although every bit of this Tang heritage is recreated, it is artistically pleasing, landscaped with ponds and lakes, classical gardens, bridges, palaces and pavilions. Explore the vast area on a golf cart, hopping on and off to see shortened operas from the Tang Dynasty days, laser shows on the lake, highly structured man-made waterfalls, as well as murals and statues of historical figures ,philosophers and poets. A 36km drive northeast takes you to Xi'an's most famous attraction, the Army of Terracotta Warriors. They were made to order in 221BC by the first emperor of China, Qin Shi Huangdi, who used the forced labour of... Question: How many historical sites in Xi'an have been referred to in the passage? - Three. - Four. - One. - Six.
Three.