Polar bears are suffering in a much {#blank#}1{#/blank#} (warm) world.

    Polar bears live in environments too cold for most animals. During much of the year, they live and hunt on the frozen Arctic sea ice. Nature has {#blank#}2{#/blank#} （prepare）them for the cold conditions. But nothing has prepared the bears for the danger {#blank#}3{#/blank#} threatens the only home they know.

    The polar bears' world is melting. Studies show that the amount of the polar ice {#blank#}4{#/blank#}（have）decreased by 9.8% every 10 years since 1978. Now about 20,000 to 25,000 polar bears live in the Arctic. Polar bears rely {#blank#}5{#/blank#} the sea ice for their survival. “The sea ice is more {#blank#}6{#/blank#} just this platform that the bears walk over,” says Andrew Derocher, {#blank#}7{#/blank#} scientist who studies North American polar bear populations. “{#blank#}8{#/blank#} it, they can't exist.”

    Some melting and refreezing of the polar ice is natural. But in a warmer world, these cycles speed up, and bears have less time {#blank#}9{#/blank#} (hunt). Normally, they have three months in the spring when they gain more weight. The extra fat is used later, when the bears are not {#blank#}10{#/blank#}(active) hunting.

—Yes, they took away all the {#blank#}1{#/blank#} there and became rich overnight.

    There is a good new for astrophiles. The last full moon of 2017 is going to appear a little bigger and brighter than most.

    Dec. 3 will bring a supermoon,{#blank#}1{#/blank#} (mean) a full moon that happens at perigee—the same time that the moon is closest to the earth.{#blank#}2{#/blank#} this particular occasion, the moon will appear 7 percent larger and 16 percent brighter than usual. Not only will this be the only full supermoon of 2017,{#blank#}3{#/blank#} it's also going to kick off a series of three full supermoons in a row. The full moons on Jan. 2 and Jan. 31 will be super {#blank#}4{#/blank#} (one) and even they'll be blue super moons,{#blank#}5{#/blank#} means the second full moon in a single month.

    While some moonwatchers might be getting excited, some people think the hype（炒作）around supermoons isn't all it{#blank#}6{#/blank#} (regard) as being. A scientist slammed（抨击）the term last year as something made up {#blank#}7{#/blank#} (complete) and a waste of everyone's time. He acknowledged that supermoons would appear bigger and brighter, but that actually an amateur {#blank#}8{#/blank#} (observe) wouldn't notice the difference. Another scientist {#blank#}9{#/blank#} (make) a similar{#blank#}10{#/blank#} (argue) back in 2012.

    If the supermoon makes you want to go out and appreciate the sky's beauty, we say “Go for it.”

    Driving to the airport in the early morning. I felt{#blank#}1{#/blank#} (excite) because I would spend the summer in Paris. While{#blank#}2{#/blank#} (look) for more interesting things to do besides sleeping and eating on the plane, I jumped at the chance to study French in this city know for{#blank#}3{#/blank#} (it) art, food and culture.

    My connecting flight(转机) was in Frankfurt, Germany, 14 hours from Denver. But when I arrived there, a feeling of anxiety{#blank#}4{#/blank#} (begin) to set in. I was very nervous {#blank#}5{#/blank#} I was in a country {#blank#}6{#/blank#} language I could not speak. But when I found my way, I gained {#blank#}7{#/blank#} (confident). When I boarded the second plane and discovered that the flight was less than an hour, I was filled{#blank#}8{#/blank#} excitement.

    When I stepped on foreign ground for the first time, I was{#blank#}9{#/blank#} (extreme) happy. I quickly had my first experience trying to communicate in {#blank#}10{#/blank#}language that I had only practised in school. As I left the airport, with one sharp turn, the Eiffel Tower came into view. I was fully in Paris.

    Tony and I are good friends. We tried to walk across the United States of America. We're not exactly sure{#blank#}1{#/blank#} we were doing it. Part of it was to test ourselves; to see if we could face the challenges. When I was{#blank#}2{#/blank#} teenager I often daydreamed that I was going to walk across the United States{#blank#}3{#/blank#} I graduated from high school.{#blank#}4{#/blank#} , I didn't do that. Before I knew it I was in my thirties, married,{#blank#}5{#/blank#} （have） a job, yet still had this idea in my mind with each{#blank#}6{#/blank#} （pass） year. I figured I was too old and my opportunity had passed. Then, a few years ago, I met Tony,{#blank#}7{#/blank#} was in his thirties and quit his job as a civil engineer in New York City to walk across the United States. He wasn't doing it for a cause{#blank#}8{#/blank#} as part of an organization. He was doing it{#blank#}9{#/blank#}（simple） because he loved to walk and discover. The idea was back and I no longer had an excuse. We planned on averaging 20miles a day and taking some days off to rest, so we expected the walk to take about 6months realizing it could take{#blank#}10{#/blank#} （long）. We were in no hurry: The total distance would have been about 3,100miles.