《2025年学霸组合训练八年级英语下册人教版浙江专版》

题目：生物结皮：长城保护的关键角色 体裁：说明文 难度：3星 建议用时：7分钟 正确率：/10
The Great Wall is more than 13,000 miles in total. As a symbol __1__ China, it is the longest wall in the world. It was finished in parts through 2,000 years. In ancient world, people __2__（usual）pressed natural materials such as soil and rocks together to build walls. It was called “rammed earth（夯土）”. In some areas, the Great Wall was built using rammed earth. Over time, wind and rain can easily break down rammed earth, __3__ scientists often wondered how these old parts of the Great Wall have remained for such a long time. A group of Chinese researchers examined a 370 - mile long part of the wall. They found that more than 2/3 of it was covered by something __4__（call）biocrusts（生物结皮）. They are thin layers（层）of different __5__（kind）of plant lives. The scientists __6__（take）some of the biocrusts back for testing. The result showed that they were __7__（strong）than rammed earth. It means biocrusts play a key role in __8__（protect）the Great Wall from erosion（侵蚀）. These findings could be important for people who study ancient structures around __9__ world. Although biocrusts may not look good, __10__（they）ability could be a very useful tool to keep ancient buildings.
1. ________ 2. ________ 3. ________ 4. ________ 5. ________
6. ________ 7. ________ 8. ________ 9. ________ 10. ________

答案： 1. of；2. usually；3. so；4. called；5. kinds；6. took；7. stronger；8. protecting；9. the；10. their