Series ID: EDKS-BASIC-ZH-0069 · Lesson No.069 · B2-Direction Information Compression
Advanced Relative Clauses and Reduced Clauses | 高级关系从句与简化从句
The students who are waiting outside can come in.
The students waiting outside can come in.
At B2 direction, relative clauses do more than identify a person or thing. They help writers control information density, add non-essential detail, connect ideas, and compress clauses when the meaning remains clear.
这一课训练的是“信息压缩与重点控制”：什么时候需要完整关系从句，什么时候可以简化，什么时候逗号会改变意思。
Chinese Edition Hub · 中文版入口 · ← Lesson No.068 · B2 Discussion, Argument and Evidence
The clause map | 从句路线
- defining vs non-defining
- who / whom / whose / which / that
- where / when
- preposition + whom/which
- object relative omission
- reduced -ing clauses
- reduced past-participle clauses
- to-infinitive reduction
- punctuation and meaning
- information density
1. Defining relative clauses | 限定性关系从句
They identify which person or thing we mean.
- The student who sits by the window is absent.
- The file that you sent is corrupted.
No commas.
2. Non-defining relative clauses | 非限定性关系从句
They add extra information about a noun already identified.
- Anna, who works in finance, will join us later.
- The report, which was published in June, has been updated.
Use commas.
3. Commas change meaning | 逗号会改变意思
Employees who work remotely need secure access.
Meaning: only the remote employees.
Employees, who work remotely, need secure access.
Meaning: all the employees are presented as remote workers. The commas make the clause extra information.
4. That in defining clauses | defining 中的 that
- The laptop that I bought is lighter.
- The person that called left no message.
That is common in defining clauses.
5. That in non-defining clauses | 非限定中不用 that
- My laptop, that I bought last year… ✗
- My laptop, which I bought last year… ✓
6. Who | who
Use for people, especially as subject:
- the teacher who explained it
7. Whom | whom
Formal object form:
- The person whom I contacted replied quickly.
In everyday English, who or omission is often more natural.
8. Whose | whose
Shows possession:
- The student whose laptop broke borrowed mine.
- The company whose offices were damaged reopened today.
Whose can refer to people and organisations/things in formal writing.
9. Which | which
- The report which explains the change is online.
- The report, which explains the change, is online.
Punctuation determines defining vs non-defining meaning.
10. Where | where
- The office where I work is moving.
- Singapore is a place where several languages are used daily.
11. When | when
- That was the year when I changed careers.
- There are times when a shorter answer is clearer.
12. Why | why
- The reason why we changed the plan was cost.
why is often optional after reason.
13. Object relative pronoun omission | 宾语关系代词可省
- The book that I bought…
- The book I bought…
Omission is possible when the relative pronoun is the object.
14. Subject relative pronoun cannot normally be omitted | 主语不能这样省
- The student works here is new. ✗
- The student who works here is new. ✓
15. Preposition at the end | 介词放句尾
Natural neutral English:
- The person who I spoke to was helpful.
- The topic which we talked about was complex.
16. Preposition before whom/which | 正式前置
More formal:
- The person to whom I spoke was helpful.
- The topic about which we spoke was complex.
17. No preposition + that in formal fronted pattern | 不能 *to that*
- The person to that I spoke… ✗
- The person to whom I spoke… ✓
18. Which referring to a whole clause | which 指整个前句
The train was cancelled, which caused a long delay.
Here which refers to the whole previous event.
19. Whole-clause which = commentary | which 可做评论
- He missed the deadline, which surprised everyone.
20. Reduced -ing clause | -ing 简化从句
Full:
The students who are waiting outside can come in.
Reduced:
The students waiting outside can come in.
21. When -ing reduction works | 什么时候可简化
Often when the full clause is active and the relative pronoun is the subject.
- People who live nearby → people living nearby
- Companies that operate internationally → companies operating internationally
22. Reduced past-participle clause | 过去分词简化
Full:
The report that was published yesterday is online.
Reduced:
The report published yesterday is online.
23. Passive meaning | 被动意义
- products made locally
- files stored online
- students selected for the programme
24. -ing vs past participle | 主动 vs 被动
- the company employing 500 people → company does the employing
- the people employed by the company → people receive the action
25. To-infinitive relative reduction | to 不定式简化
- the first person to arrive
- the next train to leave
- a problem to solve
26. First/next/only + to-infinitive | 高频结构
- She was the first student to finish.
- This is the next issue to consider.
27. Information density | 信息密度
Compare:
The report that was published by the committee last month contains recommendations that affect schools.
More compressed:
The report published by the committee last month contains recommendations affecting schools.
28. Compression is not always better | 压缩不是永远更好
Reduced clauses can make formal writing denser. Use the full clause when clarity is more important.
29. Avoid ambiguous reduction | 避免歧义
If reduction makes it unclear who performs the action or when it happens, keep the full clause.
30. Reduced clauses and time | 简化后时间信息可能减少
students studying online does not by itself show whether they studied yesterday, study now, or study generally. Context must supply the time.
31. Non-defining reduced clauses | 非限定简化
Possible in some formal contexts:
The report, published last month, has already been revised.
Commas still mark extra information.
32. Appositive-like compression | 同位信息压缩
Mei, a researcher based in Singapore, presented the findings.
This is not a relative clause, but it performs a similar information-compression job.
33. Relative clause stacking | 多层从句
Weak:
The report that was written by the team that works in the office that opened last year…
Too many embedded clauses overload the reader.
34. Split when necessary | 必要时拆句
B2 control includes knowing when not to compress.
35. Defining clause in argument | 论证中限定范围
Learners who receive regular feedback may improve faster.
The clause limits the claim to a subgroup.
36. Non-defining clause in argument | 非限定补充背景
The new policy, which was introduced in June, applies to all departments.
37. Scope must stay accurate | 范围不能改变
Removing a defining clause can accidentally broaden a claim.
38. Mandarin transfer: 中文定语常在名词前 | 英语常在名词后
Long Chinese modifiers can appear before the noun. English often places relative information after the noun, then may reduce it.
39. Mandarin transfer: “的” does many jobs | “的”不等于一个关系词
Choose who/which/whose/where/when based on grammatical relationship, not by translating 的 directly.
40. Punctuation matters more in English | 标点影响语义
Commas distinguish essential vs extra information in non-defining clauses.
41. Reading practice A | 阅读 A
The students selected for the pilot programme will receive tablets. The devices, which were purchased last month, include software designed for language learning. Teachers working with the group will collect feedback throughout the term.
- Find two reduced clauses.
- Find one non-defining relative clause.
- Which information is essential and which is extra?
42. Reading practice B | 阅读 B
The company that developed the app has released an update, which fixes several security problems. Users whose devices are older may need to install a separate patch.
- What does the first defining clause identify?
- What does whole-clause which add?
- What does whose express?
43. Rewrite practice | 改写练习
Reduce where appropriate:
- people who work remotely
- reports that were published recently
- the first student who finished
Possible answers: people working remotely / reports published recently / the first student to finish.
44. Expansion practice | 展开练习
Expand:
- students studying abroad
- products made locally
- the next issue to discuss
45. Error clinic | 常见错误
| Error | Repair |
|---|---|
| My laptop, that I bought last year… ✗ | My laptop, which I bought last year… ✓ |
| The man to that I spoke… ✗ | The man to whom I spoke… ✓ |
| The students waited outside can enter. ✗ | The students waiting outside can enter. ✓ |
| The report publishing yesterday… ✗ | The report published yesterday… ✓ |
46. First weak link diagnosis | 第一个卡点诊断
- I ignore commas → defining/non-defining meaning problem.
- I reduce active/passive incorrectly → participle-choice problem.
- I overcompress → readability problem.
- I broaden a claim by removing a defining clause → scope problem.
- I translate Chinese word order directly → noun-modifier order problem.
47. Retrieval lab | 提取练习
- 正在外面等的学生 → ______
- 昨天发布的报告 → ______
- 我联系的那个人 → ______
- 设备坏了的学生 → ______
Suggested answers: the students waiting outside / the report published yesterday / the person whom/who I contacted / the student whose device broke.
48. Seven-day training cycle | 七天训练
| Day 1 | defining/non-defining | 限定/非限定 |
| Day 2 | who/whose/which/where | 关系词 |
| Day 3 | preposition patterns | 正式结构 |
| Day 4 | -ing reduction | 主动简化 |
| Day 5 | past-participle reduction | 被动简化 |
| Day 6 | scope/punctuation audit | 范围标点 |
| Day 7 | 400-word compression edit | 综合 |
49. Self-test | 自测
Distinguish defining/non-defining clauses; use who/whom/whose/which/where/when; omit object relatives correctly; reduce active and passive clauses; use to-infinitive reductions; explain when compression changes meaning or harms clarity.
50. For parents and teachers | 给家长和老师
Teach reduction only after full relative clauses are stable.
Require learners to state whether the noun does or receives the action before choosing -ing or a past participle.
For Mandarin speakers, contrast pre-noun Chinese modification with post-noun English relative structures explicitly.
51. Final real-world challenge | 最终真实任务
- Write five defining clauses.
- Write five non-defining clauses.
- Use whose/where/when.
- Use one formal preposition + whom/which pattern.
- Reduce five active clauses.
- Reduce five passive clauses.
- Use three to-infinitive reductions.
- Run a punctuation/scope audit.
- Rewrite one dense paragraph for clarity.
- Explain why each compression is safe.
Next: Lesson No.070 | 下一课
The next lesson examines nominalisation and information density: how verbs and adjectives become nouns in formal writing, when that creates useful compression, and when it hides agency or makes prose unnecessarily heavy.
Lesson No.070 · Nominalisation and Information Density · 名词化与信息密度
Reference floor: British Council B2 Upper-intermediate · British Council B1–B2 Grammar.
