なぜやるか

関係詞節（who / which / that で始まる節）は名詞を後ろから修飾し、TOEICのPart7では1文に1〜2個含まれることが多いです。この節を [ ] で囲んで外す練習をすると、修飾元の名詞（先行詞）と主動詞の関係が見え、長文の誤読を防げます。また「who / which / that のどれを使うか」「主格か目的格か」の判断はPart5の関係代名詞問題の核心です。このLesson 6を終えると、関係詞節を含む文を正確に骨格と修飾に分解できるようになります。

やり方

関係詞節の基本

制限用法 vs 継続用法

制限用法（コンマなし）: 先行詞を限定する → [ ] で囲う
The employee [who submitted the report] was praised.

継続用法（コンマあり）: 先行詞に補足情報を加える → { } で囲う
The director, {who joined last year,} approved the plan.

関係代名詞の格

主格（〜が）: 関係詞節の中で主語の役割
the manager [who approved the plan] ← who が approved の主語

目的格（〜を）: 関係詞節の中で目的語の役割
the plan [that the manager approved] ← the manager が主語・approved の目的語は plan

例文トレーニング

文1｜who（人・主格）

原文: The analyst [who prepared the quarterly forecast] presented the results
(to the executive team).

S = The analyst
V = presented
O = the results
( ) = to the executive team
[ ] = who prepared the quarterly forecast ← analystを修飾（主格 who）

→ who は関係詞節の中で prepared の主語。

文2｜which（物・主格）

原文: The software [which automates the invoicing process] reduced manual errors
(by sixty percent).

S = The software
V = reduced
O = manual errors
( ) = by sixty percent
[ ] = which automates the invoicing process ← softwareを修飾（主格 which）

→ which は関係詞節の中で automates の主語。

文3｜that（目的格）

原文: The proposal [that the board rejected (last quarter)] has been revised
and resubmitted.

S = The proposal
V = has been revised and resubmitted
[ ] = that the board rejected (last quarter) ← proposalを修飾（目的格 that）
( ) = last quarter ← rejected を修飾（[ ]の内部）

→ that は関係詞節の中で rejected の目的語（= the proposal）。

文4｜where（場所先行詞）

原文: The conference center [where the summit was held] can accommodate
(up to five hundred participants).

S = The conference center
V = can accommodate
O = up to five hundred participants
[ ] = where the summit was held ← conference centerを修飾

→ where は the conference center（場所）を先行詞にとる。

文5｜制限用法 + 継続用法の組み合わせ

原文: The regional manager, {who joined the company (three years ago),}
approved the project [that her team had proposed (in the previous meeting)].

S = The regional manager
V = approved
O = the project
{ } = who joined the company (three years ago) ← 継続用法（補足情報）
( ) = three years ago / in the previous meeting
[ ] = that her team had proposed (in the previous meeting) ← projectを修飾

→ 継続用法 { } を外すと主節が鮮明に見える。

実戦問題

構造を分解しながら空所を埋めましょう。

Q1. The legal team reviewed all contracts ------- were submitted by the external vendors before the merger deadline.

(A) whose　(B) where　(C) that　(D) what

Q2. The engineer ------- designed the new filtration system received the company’s innovation award at the annual ceremony.

(A) which　(B) who　(C) whose　(D) whom

Q3. The branch office ------- the international clients are based will be expanded to accommodate the growing demand.

(A) which　(B) that　(C) where　(D) when

Q4. The financial projections ------- the CFO presented at the shareholder meeting were based on conservative growth assumptions.

(A) who　(B) where　(C) what　(D) which

Q5. All staff members ------- performance ratings exceeded expectations will be eligible for the annual merit bonus.

(A) whose　(B) who　(C) which　(D) that

正解一覧