北极熊需要冰。
Polar bears are in great danger.
北极熊处于极度危险之中。
Polar bears like hunting for seals to eat.
北极熊喜欢捕食海豹。
They have pushed down the number of polar bears and seals while polar bears depend on sea ice for hunting seals.
它们导致了北极熊和海豹数量的减少，而北极熊依靠海冰捕食海豹。
Polar bears catch seals to eat on the ice.
北极熊在冰上捉海豹吃。
The Arctic is the home to about 25,000 polar bears.
北极是约两万五千只北极熊的家园。
Let's take action to protect our earth and save polar bears.
让我们采取行动来保护我们的地球，拯救北极熊。
Some polar bears, however, haven't been able to get enough to eat.
然而，一些北极熊没能有足够的食物。
Scientists fly in a helicopter, over the places where polar bears live.
科学家们乘坐直升飞机，飞过北极熊的栖息地上空。
It's reported that polar bears are in danger because of global warming.
据报道，由于全球变暖，北极熊正处于危险之中。
Polar bears have to go further and work harder to find food.
北极熊必须走得更远，并更加努力地寻找食物。
What doesn't bring down the number of polar bears according to this passage?
根据这篇文章，是什么没有减少北极熊的数量？
When ice is on the ocean, the polar bears are on the hunt.
海面上有冰时，北极熊就在狩猎。
Polar bears are the largest land animals that eat meat on the planet.
北极熊是地球上最大的陆地肉食动物。
As a result, many animals are dying out, such as penguins and polar bears.
因此，许多动物正在灭绝，比如企鹅和北极熊。
There is not as much time for the polar bears to hunt for food.
北极熊没有那么多的时间猎食。
If the ice keeps becoming water, one day there might not be any polar bears.
如果冰继续融化，有一天北极熊可能就不复存在了。
Scientists want to learn all they can about polar bears and how they can help them.
科学家们想要了解关于北极熊的一切，以及如何才能帮助它们。
Most polar bears could disappear by the end of the century because of global warming, scientists say.
科学家称，由于全球变暖，多数北极熊可能会在本世纪末消失。
According to a study in Nature Climate Change, the number of most polar bears will fall rapidly by 2080.
据《自然气候变化》的一项研究显示，到2080年，几乎大多数北极熊的数量都将急剧减少。
Polar bears live in the Arctic.
北极熊生活在北极。
I'm back in Finland with the snow, reindeers, and polar bears.
我回到了芬兰，那里有雪、驯鹿和北极熊。
Biologists calculate that there are about 20,000-25,000 polar bears worldwide.
生物学家估计，全世界大概有2万至2万5千只北极熊。
Wildlife like polar bears and walruses that depend on sea ice to live is also in danger.
像北极熊和海象这样依靠海冰生存的野生动物也处于危险之中。
Global warming has posed a serious threat to the survival of animals such as polar bears.
全球变暖对北极熊等动物的生存造成了严重威胁。
Like brown bears and polar bears, sloth bears may have evolved in an environment with few trees.
和棕熊和北极熊一样，树懒熊可能是在树木稀少的环境中进化而来的。
Although polar bears' locomotion is similarly inefficient, polar bear cubs walk along with their mother.
尽管北极熊的运动能力同样低下，北极熊幼崽还是和妈妈一起前行。
Last week the scientists warned that a third of the world's polar bears could disappear in the next 40 years.
上周，科学家们警告说，世界上三分之一的北极熊可能会在未来40年里消失。
He told the brainy, sensitive, vegetarian girl next door that she couldn't come over because they were murdering polar bears.
他告诫这个住在他隔避的聪明、敏感、素食的女孩，她不能过来，因为他们正在谋杀北极熊。
Sea turtles, polar bears and giant pandas are just some of the thousands of animals in this world that are at risk of extinction.
海龟、北极熊和大熊猫只是世界上成千上万濒临灭绝的动物中的一部分。
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