Winteriscoming.It'stimeforthearcticgroundsquirrel（地...

问题详情：

     Winter is coming. It's time for the arctic ground squirrel（地松鼠) to get her underground

home ready. She chooses a quiet spot, hidden from wolves and foxes. She gathers grass and

fur to keep her home warm.

     Winter is long and cold in northern Canada.  Many days, the air is colder than the air in

your freezer. Plants can't grow, so there are no leaves or grass for animals to eat. They must

find other ways to live. The arctic ground squirrel "sleeps" the winter away.

     For months the ground squirrel has been eating lots of seeds, mushrooms, and berries.

Now she is fat. The extra fat will keep her alive through the winter.

      At last she crawls through a tunnel into the nest she has made.  She curls up, wraps her

tail around herself, and goes to "sleep". Only she won't really be sleeping. She will be

hibernating(冬眠).

     The ground squirrel's body is usually as warm as yours. When she hibernates, her body

becomes just colder than ice, but she doesn't freeze.  In the warm season, when the ground

squirrel is active, she uses most of the food she eats to make heat to stay warm.  When she

hibernates, she doesn't need much food.

    Her heart beats just one or two times each minute.  She will take only about three breaths

each minute. She won't move, even if someone touches her or shines a light into her eyes.

These changes in the ground squirrel's body let her live through the winter.

    The ground squirrel will not stay in hibernation all winter.  Her body warms up and

becomes active for a few hours once every few weeks. Over the winter, these active times use

up more than half of the energy that she worked so hard to store. Why does she do this?

Scientists aren't sure. Some think arctic ground squirrels must warm up in case their bodies

need to fight off any germs(病菌) that would make them sick.

    In April or May the arctic ground squirrel will stop hibernating. She will be skinny

because she did not eat anything during the winter. Now she will have just a few months to

have babies and fatten up before winter comes again.

28. The Arctic ground squirrel must hibernate in winter because she       

    A. needs to have a comfortable rest        B. can keep warm while hibernating

    C. must hide from wolves and foxes        D. doesn't have enough food in winter

29. While hibernating, the Arctic ground squirrel's body _  .

    A. freezes up completely                  B. is as warm as usual

    C. drops just below 0℃                     D. makes heat to stay warm

30. In winter, the Arctic ground squirrel          .

    A. doesn't breathe at all                   B. becomes active sometimes

     C.  stays in hibernation all the time         D. won't move unless touched

31. The Arctic ground squirrel is very thin usually when _          .

    A. winter comes to an end                 B. she starts to hibernate

     C. autumn is approaching                    D. she has young babies

【回答】

DCBA

知识点：阅读理解

题型：阅读理解