题目内容
Francis Collins isn't ______.
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听力原文：W: Did you enjoy visiting the museum？
M: I've been there a hundred times!
What does the man mean？
Part B
Directions: You will hear four dialogues or monologues. Before listening to each one, you will have 5 seconds to read each of the questions which accompany it. While listening, answer each question by choosing A, B, C or D. After listening, you will have 10 seconds to check your answer to each question. You will hear each piece ONLY ONCE.
听力原文： Columbus sailed from Spain in September 1492, looking for gold. Native Americans greeted him, offering gifts of corn. Columbus found little gold on that trip, but he collected many plants, including com, to bring back to Spain.
Columbus didn't know it. But the corn was much more valuable than gold. Farmers from Europe to Asia accepted it immediately. They grew it on cold mountainsides and in tropical forests. Today it feeds millions of people all over the world.
On his second trip, Columbus brought back a few chocolate beans to make chocolate. Europeans and Asians love this new drink, and soon they were paying a great deal of money for the beans. Chocolate beans became so valuable in Central America that they were used as cash for 200 years.
Tomatoes and potatoes took some time to become popular. Eventually, however, they became the basis of a lot of popular foods. It is hard to imagine life without fried potatoes or chocolate. Thanks to native American cultures, many people are able to enjoy lots of tasty food.
Why is corn feeding millions of people today？
强制性是法律固有的特征，其他社会规范不具有强制性。
Listening Device Provides Landslide(山崩；地滑；塌方)Early Warning
A device that provides early warning of a landslide by monitoring vibrations (振动)in soil is being tested by UK researchers. The device could save thousands of lives each year by warning when an area should be evacuated(疏散，撤走), the scientists say. Such natural disasters are common in countries that experience sudden, heavy rainfall(降雨，降雨量), and can also be triggered by earthquakes and even water erosion(腐蚀，侵蚀).
Landslides start when a few particles of soil or rock within a slope start to move, but the early stages can be hard to spot. Following this initial movement, "slopes can become unstable in a matter of hours or minutes, " says Nell Dixon at Southborough University, UK. He says a warning system that monitors this movement "might be enough to evacuate a block of fiats or clear a road, and save lives. "
The most common way to monitor a slope for signs of an imminent (即将发生的) landslide is to watch for changes in its shape. Surveyors can do this by measuring aside directly, or sensors(传感器) sunk into boreholes(钻孔，井眼)or fixed above ground can be used to monitor the shape of a slope. Slopes can, however, change shape without triggering a landslide, so either method is prone to causing false alarms. Now Dixon's team has developed a device that listens for the vibrations' caused when particles begin moving within a slope.
The device takes the form. of a steel pipe dropped into a borehole in a slope. The borehole is filled in with gravel(砾，沙砾，砾石)around the pipe to help transmit high-frequency vibrations generated by particles within the slope. These vibrations pass up the tube and are picked up by a sensor on the surface. Software analyses the vibration signal to determine whether a landslide may be imminent.
The device is currently being tested in a 6-metre-tall artificial clay embankment(堤岸)in Newcastle, UK. Early results suggest it should provide fewer false positives than existing systems. Once it has been carefully and thoroughly tested, the device could be used to create a complete early-warning system for dangerous slopes.
"Locations with a significant risk of landslides could definitely benefit from a machine like this, " says Adam Poulter, an expert at the British Red Cross. "As long as it doesn't cost too much, " But, Poulter adds that an early-warning system may not he enough on its own. "You need to have the human communication, " he says. "Making systems that get warnings to those who need them can be difficult. "
What does "Such natural disasters" in the first paragraph refer to？
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