Monarch butterflies

文章大意

雅思听力Part4中，一名生物系新生汇报蝴蝶的越冬生存策略，重点讲冬眠与迁徙两种方式：冬眠时代谢减慢、体内产生甘油等抗冻物质；迁徙则以帝王蝶（黑脉金斑蝶）为例，说明它无法忍受低温，天冷时成群南飞，是北美唯一进行迁徙的蝴蝶。

题目与答案

1. Hibernation

   Butterfly species have different hibernation patterns during their life cycle.

   Butterflies named “Banded Hair Freak” hibernate in the form of an 31_____ .

   答案：egg

   原文定位：For example, the banded hair freak hardly hibernates in its full-grown adult form, but as an egg

   同义替换：「the form of」↔「as」

2. A species called “Dapple White” accumulates 32_____ from larval stage.

   答案：energy

   原文定位：the dappled white, breeds during the winter in a crystallized stage, and during this time, it's able to draw on the energy it stimulated earlier on in its larval stage

   同义替换：「accumulates」↔「stimulated earlier on」

3. Slow metabolism can help them to sort out some problems in winter.

   A substance is produced in the blood which has the function as 33_____ .

   答案：antifreeze

   原文定位：They develop a substance in their blood;which serves as antifreeze, thereby adding extra resistance against lower temperatures

   同义替换：「has the function as」↔「serves as」

4. There are few predators because they can only survive in 34_____ weather

   答案：warm

   原文定位：Fewer predators exist to cause problems. This is because they're mainly active in warm weather

   同义替换：「can only survive in」↔「mainly active in」

5. Migration

   Monarch butterflies move to 35_____ in winter.

   答案：Mexico

   原文定位：The monarchs hand in their lineage to a particular region in Mexico known as the Pierre A Sequoia

   同义替换：「move to」↔「head in their lineage to」

6. To avoid cold temperature, they migrate to the south in large groups.

   The survival can help them last for up to 36_____ during a long journey.

   答案：6 months

   原文定位：In fact, the last migration generation, as reported, do for six months, which enables them to take such a long journey

   同义替换：「last for up to」↔「live for」，「during」↔「which enables them to take」

7. Monarch butterflies fly in the daytime and stay in 37_____ during night.

   答案：trees

   原文定位：These huge teams of migrating monarchs only fly during daylight hours, and at night they usually have a rest in trees

   同义替换：「daytime」↔「daylight hours」，「stay in」↔「have a rest in」，「during」↔「at」

8. Researchers found out that they orient by flying along the 38_____ .

   答案：rivers

   原文定位：It has been known for years that they find their way on the journey by following rivers

   同义替换：「orient」↔「find their way」，「flying along the」↔「following」

9. They also follow the direction of the 39_____ for navigation aid.

   答案：sun

   原文定位：the new research indicates that they may also treat the sun as a navigational aid

   同义替换：「follow the direction of」↔「as a navigational aid」

10. During migration, they mainly feed on flowers and can not reproduce.

    Recently the annual arrival of the monarchs has attracted an increasing number of 40_____ in the region.

    答案：tourists

    原文定位：Over recent years their annual arrival has gained great popularity among tourists

    同义替换：「attracted an increasing number of」↔「gained great popularity among」