Ⅰ. Circle the correct word(s) to complete the sentences.
How humans influence ecosystems
1. People (who / which) cut down forests without planting new trees are destroying the homes of wildlife.
2. The factories (who / which) pour dirty water into rivers are killing thousands of fish every day.
3. A person (who / which) throws plastic waste into the ocean harms sea animals.
4. The companies (who / which) produce too much carbon dioxide are making the Earth warmer.
How humans protect ecosystems
5. We must stop using energy (that / who) produces greenhouse gases.
6. People (who / which) are worried about the oceans pay more attention to the use of plastic bags in their daily life.
7. The documentary introduces the scientists and the research (that / which) helped save the endangered sea turtles.
8. One thing (that / who) we need to remember is: every little action makes our planet better and better.

1. who
2. which
3. who
4. which
5. that
6. who
7. that
8. that

【分析】本题考查英语定语从句中关系代词who、which、that的用法，解题关键是明确：关系代词who用于指代人，which用于指代物，that可指代人或物。解题时需先判断每个句子中被修饰的先行词（名词）是指人还是物，再匹配对应的关系代词即可。
【解析】1. 先行词People指人，故用who；2. 先行词factories指物，故用which；3. 先行词A person指人，故用who；4. 先行词The companies指物，故用which；5. 先行词energy指物，故用that；6. 先行词People指人，故用who；7. 先行词research指物，故用that；8. 先行词One thing指物，故用that。
【答案】1. who
2. which
3. who
4. which
5. that
6. who
7. that
8. that
【知识点】定语从句关系代词用法
【点评】本题为英语语法基础题，聚焦定语从句关系代词的核心用法，只要掌握先行词的属性（人/物）即可快速选出正确答案，适合初中英语学习者巩固基础。
【难度系数】0.8

Ⅱ. Rewrite the sentences after the model.
Model: Lucy’s mother bought a dress for her yesterday. Lucy likes the dress very much. →
Lucy likes the dress that her mother bought for her yesterday very much.
1. We need to save the bees. The bees help pollinate flowers. →

2. The government passed a law. The law bans single-use plastic. →

3. Rachel Carson wrote a book. The book changed the way people think about nature. →

4. There are many small actions. Small actions can help keep the fine balance of nature. →

5. The documentary A Fine Balance is very educational. We watched it in class yesterday. →

1. We need to save the bees that / which help pollinate flowers.
2. The government passed a law that / which bans single-use plastic.
3. Rachel Carson wrote a book that / which changed the way people think about nature.
4. There are many small actions that / which can help keep the fine balance of nature.
5. The documentary A Fine Balance that / which we watched in class yesterday is very educational.

【分析】
本题要求将两个简单句合并为含定语从句的复合句，解题思路为：1. 定位两个句子中重复出现的名词（即先行词）；2. 因先行词均指物，选用关系代词that/which；3. 将修饰先行词的句子作为定语从句置于先行词后，调整语序使句子通顺。
【解析】
1. 先行词为the bees（指物），用that/which引导定语从句修饰bees，合并为We need to save the bees that / which help pollinate flowers.
2. 先行词为a law（指物），用that/which引导定语从句，合并为The government passed a law that / which bans single-use plastic.
3. 先行词为a book（指物），用that/which引导定语从句，合并为Rachel Carson wrote a book that / which changed the way people think about nature.
4. 先行词为many small actions（指物），用that/which引导定语从句，合并为There are many small actions that / which can help keep the fine balance of nature.
5. 先行词为The documentary A Fine Balance（指物），用that/which引导定语从句，合并为The documentary A Fine Balance that / which we watched in class yesterday is very educational.
【答案】
1. We need to save the bees that / which help pollinate flowers.
2. The government passed a law that / which bans single-use plastic.
3. Rachel Carson wrote a book that / which changed the way people think about nature.
4. There are many small actions that / which can help keep the fine balance of nature.
5. The documentary A Fine Balance that / which we watched in class yesterday is very educational.
【知识点】
定语从句、句子合并
【点评】
本题聚焦定语从句的基础应用，是英语句式转换的核心基础题型，需掌握关系代词that/which修饰指物先行词的用法，考查难度适中。
【难度系数】
0.6