Defining or Non-defining Relative Clauses
Review how defining and non-defining clauses organise identifying and extra information before compressing noun descriptions.
ทบทวนการจัดข้อมูลระบุคำนามและข้อมูลเสริมก่อนย่อคำบรรยายคำนามให้กระชับ
TF30 · B2 Grammar · 30 min
Reduced Relative Clauses
Compress detailed noun descriptions with -ing, past participles and to-infinitives while protecting the meaning the listener still needs.
Why this lesson matters · เหตุผลที่เรียนบทนี้
For learners: Compress detailed noun descriptions so a listener can compare options quickly without losing who acted, who was affected, or why one option matters.
For teachers: The lesson moves from full-clause recovery to active, passive and infinitive reductions, then requires a keep-full decision, listening reconstruction and an independent shortlist recommendation.
สำหรับผู้เรียน: ย่อคำบรรยายคำนามให้กระชับเพื่อเปรียบเทียบตัวเลือกได้เร็ว โดยยังรักษาความหมายว่าใครเป็นผู้ทำ ใครเป็นผู้ถูกกระทำ และเหตุผลสำคัญของแต่ละตัวเลือก
สำหรับครู: บทเรียนเริ่มจากกู้ความหมายของประโยคเต็ม ฝึกย่อแบบ active, passive และ infinitive ตัดสินใจเมื่อใดต้องเก็บรูปเต็ม แล้วนำไปฟัง ขยายความ และแนะนำ shortlist อย่างอิสระ
Your Goal
Reduce six full relative clauses into accurate -ing, past-participle and to-infinitive phrases, keep two clauses full when reduction would hide needed meaning, and use the choices to explain a three-option shortlist.
คำอธิบายภาษาไทย
ย่อ relative clause ด้วย -ing, past participle และ to-infinitive เมื่อความสัมพันธ์ยังชัด พร้อมตัดสินใจเก็บรูปเต็มเมื่อการย่อจะทำให้เวลา modal หรือผู้กระทำสำคัญหายไป แล้วนำไปอธิบายตัวเลือกสามแบบอย่างกระชับ
Why this lesson matters
Professional descriptions often contain several details. Reduction makes them easier to scan: “the candidates who are waiting outside” becomes “the candidates waiting outside”. But shorter is not always clearer. “the applicant who can start Monday” must normally stay full because reducing it would remove can.
ภาษาไทย: การย่อช่วยให้คำบรรยายคน เอกสาร และตัวเลือกกระชับขึ้น แต่ต้องตรวจว่าความหมายสำคัญยังอยู่ หาก tense, modal หรือผู้กระทำจะหายไป ควรเก็บ relative clause แบบเต็ม
PROGRESS FOCUS What improves today?
MEAN · MeaningProtect who acts, who is affected, and any tense, modal or actor information the listener needs.
FORM · FormChoose noun + -ing, noun + past participle or noun + to-infinitive, and attach the phrase to the correct noun.
USE · Real useCompare three options concisely, answer a clarification question and repair one unsafe reduction.
Your 30-minute route
1 · 4 minRecover the full meaning
2 · 4 minControl active and passive
3 · 5 minChoose infinitive or keep full
4 · 5 minListen, expand and evaluate
5 · 5 minBuild a concise shortlist
6 · 7 minRecommend, clarify and retry
Teacher Lesson Plan
Begin with the full clause. Ask three questions before reducing: “Which noun does it describe? Who performs or receives the action? What meaning would disappear?”
| Stage | Teacher move | Evidence to collect |
|---|---|---|
| 1 · Meaning | Expand every reduced phrase before naming its pattern. | Six noun–relationship maps |
| 2 · Control | Contrast an active -ing phrase with a passive participle phrase beside the noun. | Four accurate reductions |
| 3 · Decide | Require a meaning reason for each to-infinitive or keep-full decision. | Five decisions + reasons |
| 4 · Listen | Play each shortlist for gist, then replay for full-clause reconstruction. | Two listening records |
| 5 · Build | Check attachment and lost meaning before correcting style. | Three-option shortlist |
| 6 · Perform | Score the first recommendation, give one MEAN/FORM/USE target and allow a focused retry. | Independent recommendation |
Stage 1 · Recover the full meaning
Begin with the noun and relationship. A safe reduction must preserve who acts, who is affected or what special role the noun has.
STUDENT TASK
FULL CLAUSE
Who performs the action?
The candidates who are waiting outside have interviews at two.
The candidates act → waiting outside.FULL CLAUSE
Who receives the action?
The documents that were submitted today need checking.
The documents are affected → submitted today.- Underline the noun and box its full relative clause.
- Label the relationship active, passive or special role/order.
- Say the reduced version, then expand it back to prove the meaning survives.
Quick meaning testExpand “the first candidate to complete the task”. Which full clause and order meaning does it contain?
Finish evidenceSix noun–relationship maps that can be expanded back into accurate full clauses.
Teacher Help · Stage 1
Do not teach deletion as a mechanical trick. Require the learner to name the noun and relationship first. If the expanded clause cannot be recovered accurately, keep it full until the meaning is secure.
Stage 2 · Control active and passive reductions
Use -ing when the noun performs the action and a past participle when the noun receives it.
STUDENT TASK
| Relationship | Safe pattern | Full → reduced |
|---|---|---|
| Active | noun + verb-ing | people who work remotely → people working remotely |
| Passive | noun + past participle | proposals that were approved yesterday → proposals approved yesterday |
The attachment check
Place the reduced phrase immediately beside the noun it describes.
Unsafe: “We reviewed in the meeting the proposal submitted yesterday.” Clearer: “We reviewed the proposal submitted yesterday in the meeting.”
- Reduce two active clauses with -ing.
- Reduce two passive clauses with a past participle.
- Place each phrase beside its noun and expand it back to check the relationship.
Finish evidenceFour accurate active/passive reductions with safe attachment.
Teacher Help · Stage 2
Use expansion to diagnose errors: “people working” must recover “people who are working”, while “documents submitted” must recover “documents that were submitted”. Correct relationship and attachment before spelling.
Stage 3 · Choose a to-infinitive or keep the clause full
Use a to-infinitive for clear order, role or purpose meanings. Keep the full clause when reduction would remove tense, modal meaning or an important actor.
STUDENT TASK
Choose reduce or keep full. Then give a meaning reason.
| Full description | Your decision | Meaning reason |
|---|---|---|
| the first supplier that confirms the price | the first supplier to confirm the price | Clear order meaning after first. |
| a tool that teams can use to compare costs | a tool to compare costs | Clear purpose; the general user is understood. |
| the applicant who can start Monday | Keep full | The modal can is essential. |
| the report that the finance team revised | Keep full | The actor matters; “report revised” would hide it. |
| Maya, who has managed the region since 2022 | Keep full | The present-perfect time connection matters. |
Check the decision rule
Reduce only when the shorter phrase preserves the relationship and necessary information. Keep the full clause when a modal, important actor or time relationship would disappear. Concision is useful only when meaning remains recoverable.
Finish evidenceFive reduce/keep-full decisions with a meaning reason for each.
Teacher Help · Stage 3
Reject a shorter answer if it loses meaning. Ask the learner to expand the proposed reduction: if the original modal, actor or time relationship cannot be reconstructed, the full relative clause is the safer choice.
Stage 4 · Listen, expand and evaluate
Recover the full clause behind each reduced phrase, then decide whether any important information has been lost.
STUDENT TASK
Shortlist A · CandidatesBritish English · Brian Neural
First listen: identify the preferred candidate. Second listen: capture and expand each reduced phrase.
Shortlist B · VenuesAmerican English · Joanna Neural
First listen: identify the preferred venue. Second listen: find the intentionally full clause and explain why it stays full.
- Record the shortlist decision from each audio.
- Write each reduced phrase beside the noun it describes.
- Expand it into a full relative clause and label the relationship.
- Identify one clause kept full and explain what meaning it protects.
Finish evidenceTwo listening records: decision, reduced phrase, full clause and safety reason.
Teacher Help · Stage 4
Play each shortlist once for the decision and once for language evidence. Do not reveal the transcript first. Use both accents for listening variety; they are not imitation targets.
Stage 5 · Build a concise three-option shortlist
Compress repeated detail so a listener can compare options quickly without losing an important reason.
STUDENT TASK
Required language
Option 1: one active -ing phrase · Option 2: one passive participle phrase · Option 3: one to-infinitive phrase · Keep one clause full to protect a modal, actor or time meaning.
- Choose three realistic candidates, venues, products or services.
- Write two full relative clauses for each option.
- Reduce only the clauses that pass the meaning and attachment checks.
- Give the shortlist to a partner. The partner expands two phrases and challenges one risky reduction.
Attachment challengeRepair: “We shortlisted for the second interview the candidate leading the bilingual team.” Keep the reduced phrase beside candidate.
Check the repair
We shortlisted the candidate leading the bilingual team for the second interview. The phrase now sits beside the noun it describes.
Finish evidenceA three-option shortlist with all three reduction types, one intentionally full clause and one attachment repair.
Teacher Help · Stage 5
Let the partner expand two phrases before correcting. If expansion produces the wrong actor or relationship, return to the full clause. Choose one high-value repair rather than correcting every style issue.
Stage 6 · Final Practice: recommend, clarify and retry
Use concise noun descriptions independently while preserving every detail needed for a fair shortlist decision.
FINAL PRACTICE
Plan → compare → recommend → clarify → repair → retry
- Select three real or realistic candidates, venues, products or services.
- Plan only short notes: option · active detail · passive detail · role/order detail · meaning that must stay full.
- Give a 90–120 second recommendation using at least one -ing phrase, one past-participle phrase, one to-infinitive phrase and one intentionally full relative clause.
- Your partner expands one phrase and asks: “Who performed that action?” or “What meaning would be lost if you reduced that clause?”
- Repair one unsafe or misplaced phrase, then retry only the affected comparison.
Planning example: candidate leading a bilingual team · portfolio reviewed by the director · first applicant to complete the task · applicant who can start Monday.
Score the first independent performance
MEAN · MeaningThe listener can recover who acts, who is affected and why any full clause remains necessary.
FORM · FormThe learner controls -ing, past-participle and to-infinitive reductions and attaches every phrase to the correct noun.
USE · Real useThe comparison supports a clear recommendation and the learner repairs one unsafe reduction after clarification.
0 · Not yetA reduction changes the relationship, loses needed meaning or attaches to the wrong noun.
1 · With supportThe shortlist becomes clear after an expansion prompt, attachment cue or model.
2 · IndependentMeaning, all three reduction forms and the recommendation remain clear without teacher-supplied sentences.
Result: 0–2 Rebuild · 3–4 Developing · 5–6 B2 mastery evidence.
Finish evidenceFirst recommendation + partner expansion + clarification answer + one focused retry.
Teacher Help · Stage 6
Score the first independent attempt across MEAN, FORM and USE. Give one target only: relationship, reduction form, lost meaning or attachment. Preserve the first score and note whether the focused retry improves that target.
Grammar you can use
You can now compress detailed noun descriptions with three reduction patterns, keep a full relative clause when important meaning would disappear, and use those decisions to compare and recommend options clearly. Continue through the Dynamic Learning Graph below.
Return to the Learning LibraryContinue your learning path
Past Participle Clauses
Compare reduced relative clauses with broader past-participle clause meanings, especially safe attachment.
เปรียบเทียบ reduced relative clause กับความหมายที่กว้างขึ้นของ past-participle clause โดยเน้นการวางวลีข้างคำนามที่ถูกต้อง
Objective and Subjective Description
Use concise objective details when separating observable evidence from personal impressions.
ใช้รายละเอียดที่กระชับเมื่อต้องแยกข้อมูลที่สังเกตได้ออกจากความเห็นส่วนตัว
B2 Grammar Mastery: Precision Under Pressure
Prove B2 grammar control by integrating concise descriptions into a precise briefing under pressure.
พิสูจน์การควบคุมไวยากรณ์ B2 ด้วยการผสานคำบรรยายกระชับในภารกิจ briefing ที่ต้องตอบสนองอย่างแม่นยำ
