Polar bears are suffering in a【C1】________(warm)world than ever before. Polar bears live in environments too cold for most a

admin2021-12-30  10

问题     Polar bears are suffering in a【C1】________(warm)world than ever before.
    Polar bears live in environments too cold for most animals. During much of the year. 【C2】________live and hunt on the frozen Arctic sea ice. Nature has prepared them for the cold conditions. But nothing has prepared the bears for the danger threatening the only home they know.
    The polar bears ’ world is【C3】m________.  Studies show that the   polar ice【C4】________(reduce) by 9. 8% every 10 years since 1978. Now about 20,000 to 25,000 polar bears live in the Arctic. Polar bears 【C5】d________on the sea ice for their survival.
    "The sea ice is more than just this platform that the bears walk over. " says Andrew Durocher, a scientist【C6】________ studies North  American  polar  bear  populations." 【C7】________it, they can’ t exist. "
    Some melting and refreezing of the polar ice is natural. 【C8】________, in a warmer world, these cycles speed up, and bears have less time 【C9】________(hunt). Normally. they have three months in the spring when they gain more weight. The extra fat is used later, 【C10】________the bears are not actively hunting.
【C4】

选项

答案has reduced

解析 从该句话的since 1978可以得知,本题考查现在完成时的用法,故答案是has reduced。
转载请注明原文地址:https://jikaoti.com/ti/KeLMFFFM
0

随机试题
最新回复(0)