四、李明介绍了大自然的鬼斧神工——喀斯特地貌。根据首字母提示写出单词，一起来了解一下吧！
Have you ever seen those tall, pointed mountains that look like something from a fairy tale? Or explored huge caves full of strange shapes? These are part of karst landscapes(喀斯特地貌), a natural wonder that China is famous for.
Karst is a special landform formed over millions of years. When rainwater, which is slightly acidic(酸性的), falls on limestone(a type of rock), it s 1 breaks down the rock. This process（过程）c 2 amazing shapes on the surface and underground. In China, you can find some of the most breathtaking karst scenery in the world.
The Stone Forest(Shilin) in Yunnan is a fantastic e 3. It looks like a real forest made of stone! Walking through it, you will be amazed by the countless stones. Local Yi people even have a famous festival there. A 4 world-famous site is the South China Karst in Guilin and Yangshuo. The landscape there has the feature of green-covered karst hill standing along the beautiful Lijiang River. It is so beautiful that it appears on the b 5 of the 20-yuan Chinese banknote. Taking a boat trip along the river is like travelling t 6 a Chinese painting.
B 7 the beautiful surface views, karst areas also hide unbelievable underground worlds, such as the Reed Flute Cave in Guilin. Inside, you can see so many rocks in unusual shapes—some hang down, and others point upwards. All lit up by c 8 lights, red, blue, pink and so on.
These karst landscapes are not just beautiful; they are also v 9 for scientific research. However, they face threats(威胁) from too much p 10 and tourism. Protecting these natural wonders is very important so that future generations can also enjoy their beauty.
1. 2. 3. 4. 5.
6. 7. 8. 9. 10.

1. slowly 2. creates/causes 3. example 4. Another 5. back 6. through 7. Besides 8. colourful 9. valuable 10. pollution

【分析】
这是一道首字母填空题，解题思路为：先通读全文把握文章主题（介绍喀斯特地貌），再结合每个空格所在句子的语境、语法结构（如词性、时态、主谓一致等）及首字母提示，推断符合要求的单词，最后验证所填单词是否契合上下文逻辑。
【解析】
1. 空格处修饰动词短语breaks down，需用副词，结合句意“略带酸性的雨水慢慢分解岩石”及首字母s，填slowly。
2. 空格处作谓语，主语是单数process，时态为一般现在时，需用动词第三人称单数形式，结合句意“过程形成惊人形状”及首字母c，填creates/causes。
3. 空格处被形容词fantastic修饰，需用名词，结合句意“石林是极好的例子”及首字母e，填example。
4. 空格处修饰可数名词site，表“另一个”，结合句意“另一个世界闻名的景点”及首字母A，填Another。
5. 空格处位于定冠词the后，需用名词，结合句意“出现在20元人民币背面”及首字母b，填back。
6. 空格处需用介词，结合句意“像在中国画里穿行”及首字母t，填through。
7. 空格处表“除……之外（还有）”，结合句意“除了地表景观还有地下世界”及首字母B，填Besides。
8. 空格处修饰名词lights，需用形容词，结合句意“五颜六色的灯光”及首字母c，填colourful。
9. 空格处作表语，需用形容词，结合句意“对科学研究有价值”及首字母v，填valuable。
10. 空格处位于形容词too much后，需用不可数名词，结合句意“来自过多污染的威胁”及首字母p，填pollution。
【答案】1. slowly 2. creates/causes 3. example 4. Another 5. back 6. through 7. Besides 8. colourful 9. valuable 10. pollution
【知识点】首字母填空、词汇运用、语境分析
【点评】本题以喀斯特地貌为话题，考查学生的词汇储备及语境理解能力，要求结合语法规则和上下文逻辑推断单词，是常见的英语基础题型，难度适中。
【难度系数】0.6

五、Millie 最近学习了关于珊瑚礁的知识，她准备介绍与其相关的内容参加比赛。根据括号内的提示写出单词，补全她的介绍。
A coral reef is a busy underwater world. Tiny coral animals work together to 1（创造）huge, rocky structures. You can find these beautiful places in warm seas 2（几乎）all around the world. It's a 3（吵闹的）and lively neighbourhood for thousands of fish. However, 4(/ˈklaɪmət/) change is making the ocean too warm, which harms the coral. This is a big problem we need to 5（deal with）. If we don't protect them, these amazing reefs might disappear. We
Unit 7 | The natural world
can help by learning more and keeping the oceans clean. Saving the coral reefs means saving a wonderful part of our planet.
1. 2. 3. 4. 5.

1. create 2. almost 3. noisy 4. climate 5. solve

【分析】
本题需根据括号内的中文提示或音标，结合句子的语法结构（如不定式、并列结构等）填写正确单词。解题时先分析每个空的句子成分确定所需词性，再结合提示或音标匹配对应英语单词，注意单词形式（如不定式用原形）。
【解析】
1. 空格前是不定式符号to，需填动词原形，中文提示“创造”对应动词create；
2. 空格修饰短语all around the world，需填副词，中文提示“几乎”对应副词almost；
3. 空格与lively并列修饰neighbourhood，需填形容词，中文提示“吵闹的”对应形容词noisy；
4. 根据音标/ˈklaɪmət/，对应单词climate；
5. 空格前是不定式符号to，需填动词原形，结合语境“解决问题”，对应单词solve。
【答案】
1. create 2. almost 3. noisy 4. climate 5. solve
【知识点】
动词的用法、副词的用法、形容词的用法
【点评】
本题考查基础词汇的运用，结合句子结构和提示填写单词，难度适中，适合巩固基础词汇。
【难度系数】
0.6