B1 · 中級 チャプター 9

表現の幅が広がる！関係代名詞で「あの人・その物」を詳しく説明しよう

6 トータルルール
70 例文
6 分
このチャプターのルール クイック練習

Chapter in 30 Seconds

Unlock the power of relative clauses to connect your ideas and describe your world with precision.

  • Identify the correct relative pronouns for people and objects.
  • Construct defining relative clauses to clarify your meaning.
  • Apply the 'that' shortcut to sound more natural in conversation.
Connect your world with confidence.

学べること

英語を話していて「もっと詳しく説明したいのに、文がぶつ切りになっちゃう…」と感じたことはありませんか？この章では、そんな悩みを解決する『関係代名詞』をマスターします！ 人には who、物には which、そしてどちらにも使える万能な that。これらを使いこなせば、「昨日会った友人」や「私が探している鍵」のように、特定の情報を一言でスムーズに付け加えられるようになります。例えば、職場で「私が昨日送った資料（The file that I sent yesterday）」について正確に伝えたり、パーティーで「赤い帽子を被っている人」を教えたりする時に欠かせないスキルです。 さらに、中級者として知っておきたい「thatを省略してこなれて見せるテクニック」や、逆に「ここは省略厳禁！」という重要なルールもセットで学びます。この章を終える頃には、短く幼稚な文から卒業し、ネイティブのような流暢で豊かな表現ができるようになりますよ。さあ、一緒にステップアップしましょう！

Learning Objectives

By the end of this chapter, you will be able to:

  1. 1
    By the end you will be able to: Use relative pronouns to describe people and objects in a professional context.

チャプターガイド

Overview

Do you ever find yourself struggling to clearly identify people or describe objects when speaking English? Mastering how to connect your thoughts smoothly is a game-changer for B1 English grammar, especially when you want to sound more natural and confident. This guide will help you precisely identify people and things, making your descriptions effortless and your communication much clearer.
You'll learn the specific uses of who, which, and that – these are your secret weapons for building more sophisticated sentences. We’ll also explore defining relative clauses, which act like essential ID tags for the nouns you're talking about, and even uncover a clever shortcut that native speakers use all the time! Get ready to polish your English identifying people and things skills and impress with your improved fluency.

How This Grammar Works

At the heart of identifying people and things smoothly are relative pronouns. They act like bridges, connecting extra information to a noun. For people, we almost exclusively use who.
For example,
The woman who answered the phone was very helpful.
Here, who connects answered the phone to The woman, telling us exactly *which* woman. When you're talking about things or even animals, which is your go-to.
I found the book which you lent me yesterday.
This tells us specifically *which* book.
Now, for a versatile option: that. You can use that for *both* people and things, but only in defining relative clauses. These clauses provide essential information about the noun; without them, the sentence’s meaning would change or be unclear.
They *never* take commas. For instance,
The student that won the award studied very hard
(referring to a person). Or,
This is the car that needs to be repaired
(referring to a thing).
A key distinction comes with dropping these pronouns. When the relative pronoun (like who, which, or that) is the subject of the relative clause – meaning it performs the action – you cannot drop it. Look at
The chef who cooked our meal is famous.
Who is the subject of cooked, so it must stay.
However, you *can* drop the relative pronoun when it's the object of the verb in the relative clause. This is the that shortcut. For example,
This is the movie (that) I watched last night.
Here, that is the object of watched (I watched *that* movie), so it can be omitted. This makes your English sound much more fluid and natural.

Common Mistakes

  1. 1✗ The person which called me was my sister.
✓ The person who called me was my sister.
*Explanation:* Remember to always use who when referring to people. Which is for things or animals.
  1. 1✗ The report I wrote was very long. (Intended as subject pronoun omitted)
✓ The report that I wrote was very long. OR The report which I wrote was very long.
*Explanation:* While you *can* drop object relative pronouns, you cannot drop a subject relative pronoun. If the pronoun is followed by a verb (e.g.,
The car *that* *is* parked outside...
), it's the subject and cannot be omitted. In the corrected example, 'I' is the subject of 'wrote', so the relative pronoun 'that' or 'which' is the object and *can* be dropped (making
The report I wrote was very long
also correct, but the mistake here was thinking it was a subject pronoun drop). A better example of a subject drop mistake:
✗ The dog barked loudly chased the squirrel.
✓ The dog that barked loudly chased the squirrel.
*Explanation:* Here, that is the subject of barked and performs the action, so it cannot be dropped.
  1. 1✗ My new phone, that I bought yesterday, is very fast.
✓ My new phone, which I bought yesterday, is very fast.
*Explanation:* The pronoun that is typically used only in *defining* relative clauses (no commas). If the information is extra or non-essential (often indicated by commas), use which.

Real Conversations

A

A

Hey, do you know the student who just presented the project?
B

B

Yes, she’s the one that I mentioned yesterday, the one who helped me with my research.
A

A

Did you find the keys which you lost this morning?
B

B

Not yet! I’m looking for the bag that I took to the gym. I think they might be inside.
A

A

Have you met our new team member? She's the person who designed the new website layout.
B

B

Oh, yes! I heard about the fantastic work (that) she did. Her portfolio, which I saw online, was very impressive.

Quick FAQ

Q

When can I drop 'that' or 'which' in a sentence?

You can drop that or which when they are the object of the verb in the relative clause. For example,

This is the book (that) I read.
Here, 'I' is the subject of 'read', so 'that' is the object and can be omitted.

Q

Is 'that' always interchangeable with 'who' or 'which'?

Not always! While that can often replace who or which in *defining* clauses, it cannot be used in *non-defining* clauses (those with commas). Also, who is exclusively for people, and which for things (especially in formal contexts or non-defining clauses).

Q

Do defining relative clauses need commas?

No, defining relative clauses never use commas. They provide essential information that identifies the noun, and the sentence's meaning would change or be unclear without them.

Q

Can I use 'which' for animals?

Yes, you can use which for animals, especially when you are referring to them as things rather than giving them human-like qualities. For example,

The dog which won the race was very fast.

Cultural Context

Native English speakers use these relative pronoun patterns constantly in daily communication. You'll often hear that used quite broadly for both people and things in informal speech, even when who or which would be grammatically correct. The dropping the pronoun shortcut is extremely common in spoken English when the pronoun is the object – it makes sentences flow much more naturally and quickly. While formal writing might prefer who for people and which for things (especially in non-defining clauses), in casual conversation, don't be surprised to hear more flexibility.

重要な例文 (8)

1

Do you know the student `who` sits in the front row?

一番前の席に座っている生徒を知っていますか？

関係代名詞: 人を表す 'Who' の使い方
2

I just talked to the customer service rep `who` helped me with my order.

今、私の注文を手伝ってくれたカスタマーサービスの担当者と話しました。

関係代名詞: 人を表す 'Who' の使い方
3

The phone `which is ringing` is mine.

鳴っている電話は私のものです。

関係代名詞: 'Which'（物について）
4

She bought a dress `which was on sale`.

彼女はセールになっていたドレスを買いました。

関係代名詞: 'Which'（物について）
5

This is the app that helps me learn Spanish.

これは、スペイン語学習に役立つアプリです。

関係代名詞: 人と物への 'That' の使い方
6

The student that asked the question got extra credit.

質問をした生徒は追加の成績をもらいました。

関係代名詞: 人と物への 'That' の使い方
7

The barista who made my coffee smiled.

私のコーヒーを作ってくれたバリスタさんが微笑みました。

限定関係詞節：人や物を特定する
8

I bought the shoes that were on sale.

セールになっていた靴を買いました。

限定関係詞節：人や物を特定する

ヒントとコツ (4)

💡

人には 'who'、物には 'which' を使いましょう。

これはとてもシンプルなルールですが、一番大切です！人間について話す時は常に 'who' を選んでください。物や概念、動物（擬人化しない場合）には 'which' を使います。
I know a person who speaks three languages, but I read a book which changed my life.
frontend.learn_grammar.from_rule: 関係代名詞: 人を表す 'Who' の使い方
💡

Which for Clarity

どれを指しているか、はっきりさせたい時に「which」を使ってみましょう。特に、いくつか選択肢がある場合に、誤解なく伝えられます。「Use which to precisely identify *which* specific thing you're talking about, especially when there are multiple possibilities. It helps remove ambiguity from your sentences.」
frontend.learn_grammar.from_rule: 関係代名詞: 'Which'（物について）
💡

「不可欠な情報」を考えよう

「that」で始まる節が、名詞を特定するために絶対に必要なら、その使い方は正しいです。もしその節を削除しても文が成立するなら、「that」は間違っている可能性があります。「The student that asked the question got extra credit.」
frontend.learn_grammar.from_rule: 関係代名詞: 人と物への 'That' の使い方
💡

「絶対に必要な情報」だと考えてね💡

関係代名詞節をなくしても文の意味が曖昧になるなら、それは限定関係代名詞節です。ただの追加情報ではなく、「そのものズバリ」の情報なんですよ！「If you remove the relative clause and the sentence's meaning becomes unclear, you're dealing with a defining relative clause.」
frontend.learn_grammar.from_rule: 限定関係詞節：人や物を特定する

重要な語彙 (5)

Identify to distinguish Relative connected to Pronoun word replacing a noun Clause part of a sentence Omit to leave out

Real-World Preview

briefcase

Office Introduction

Review Summary

  • Person + who + verb
  • Thing + which + verb
  • Noun + (that/which) + Subject + Verb

よくある間違い

Use 'who' for people, not 'which'.

Wrong: The man which lives there.
正解: The man who lives there.

Don't repeat the object pronoun (it).

Wrong: The car that I like it is red.
正解: The car that I like is red.

Avoid redundant pronouns in relative clauses.

Wrong: The person that I met him.
正解: The person that I met.

このチャプターのルール (6)

1

関係代名詞: 人を表す 'Who' の使い方

B1
人を説明する時に大切な情報を自然に足せる「who」は、英語を「自然」で「明確」にする魔法の言葉ですよ。
Do you know the student `who` sits in the front ro...
12 例文
2

関係代名詞: 'Which'（物について）

B1
「which」を使うと、物、動物、考えについて、「which」で「自然に」「重要な情報」を追加できるんですよ！
The phone `which is ringing` is mine.
12 例文
3

関係代名詞: 人と物への 'That' の使い方

B1
「that」は日常英語で人や物を説明するときにとても役立つ「万能」な関係代名詞ですよ。
This is the app that helps me learn Spanish.
12 例文
4

限定関係詞節：人や物を特定する

B1
限定関係代名詞は、「どの人」「どの物」について話しているのかを「正確に特定」するための「魔法のツール」なんです！
The barista who made my coffee smiled.
12 例文
5

主語を省略しない：関係代名詞 (who, which, that)

B1
関係代名詞が節の「主語」の場合は、絶対に「who」「which」「that」を「省略しない」でね！
This is the student who always asks insightful que...
12 例文
6

関係代名詞の省略 ('that'のショートカット)

B1
関係代名詞が目的語の時にthatを省略すると、英語がもっと「自然」に聞こえますよ！簡単！
This is the book I was reading last week.
10 例文

Next Steps

You are doing amazing work! Keep practicing these structures and you will be a fluent speaker in no time.

Write a paragraph describing your favorite room.

Continue to: Describing Places, Times, and Ownership

クイック練習 (10)

正しい形を選びましょう。

I need the book ___ is on the top shelf.

✓ Correct! ✗ Not quite. Correct answer: which
「book」（本）は物なので、「which」が正しい関係代名詞です。

frontend.learn_grammar.from_rule: 関係代名詞: 'Which'（物について）

関係代名詞thatを省略できるなら省略して、文を完成させましょう。

This is the gift ___ my friend gave me.

✓ Correct! ✗ Not quite. Correct answer:
ここでは「my friend」が「gave」の主語なので、that（またはwhich）は目的語です。より自然に聞こえるように、完全に省略できますよ。

frontend.learn_grammar.from_rule: 関係代名詞の省略 ('that'のショートカット)

文の間違いを見つけて修正しましょう。

Find and fix the mistake:

The person stole my wallet ran away.

✓ Correct! ✗ Not quite. Correct answer: The person who stole my wallet ran away.
「The person」は「stole」の主語です。関係節の主語である関係代名詞（whoやthat）を省略することはできません。

frontend.learn_grammar.from_rule: 関係代名詞の省略 ('that'のショートカット)

正しい関係代名詞を選んでください。

The person ___ helps me with tech is very patient.

✓ Correct! ✗ Not quite. Correct answer: who
ここでは「who」が人を指し、節の主語になっていますね。「that」も正解ですが、「who」も良い選択肢です。

frontend.learn_grammar.from_rule: 限定関係詞節：人や物を特定する

間違いを見つけて修正してください。

The book which was missing found its way back.

✓ Correct! ✗ Not quite. Correct answer: The book that was missing found its way back.
元の文は実は正解です！「which」は「was missing」の主語なので省略できません。「that」の選択肢も、限定用法の節では「which」の代わりに「that」が使えるため正しいです。

frontend.learn_grammar.from_rule: 主語を省略しない：関係代名詞 (who, which, that)

正しい関係代名詞を選びましょう。

The woman ___ lives next door is a doctor.

✓ Correct! ✗ Not quite. Correct answer: who
'The woman' は人なので、'who' を使って説明するのが正しいです。

frontend.learn_grammar.from_rule: 関係代名詞: 人を表す 'Who' の使い方

関係代名詞が正しく使われている、または省略されている文を選びましょう。

Choose the correct sentence:

✓ Correct! ✗ Not quite. Correct answer: The food that tastes good is often unhealthy.
正しい文では、thatは「tastes good」の主語なので、残しておく必要があります。関係節の主語は省略できません。

frontend.learn_grammar.from_rule: 関係代名詞の省略 ('that'のショートカット)

関係代名詞を主語として正しく使っている文を選んでください。

正しい文を選んでください：

✓ Correct! ✗ Not quite. Correct answer: The car which broke down is mine.
「Which」は「broke down」の主語であり、省略できません。他の選択肢は文法的に間違っています。

frontend.learn_grammar.from_rule: 主語を省略しない：関係代名詞 (who, which, that)

間違いを見つけて修正しましょう。

Find and fix the mistake:

The person which called me was very rude.

✓ Correct! ✗ Not quite. Correct answer: The person who called me was very rude.
「which」は物、動物、考えに使います。人には「who」を使うべきです。

frontend.learn_grammar.from_rule: 関係代名詞: 'Which'（物について）

「that」が正しく使われている文を選びましょう。

正しい文を選んでください：

✓ Correct! ✗ Not quite. Correct answer: She's the friend that lives across the street.
「that」は制限用法で人を指すことができます。情報が不可欠なのでカンマは不要です。

frontend.learn_grammar.from_rule: 関係代名詞: 人と物への 'That' の使い方

Score: /10

よくある質問 (6)

関係代名詞は、ある節（主語と動詞がある語のまとまり）を名詞や代名詞につなげる言葉です。その名詞に関する追加情報を示します。例えば、「一生懸命勉強する生徒は良い成績を取ります」は
The student who studies hard gets good grades.
と言いますよ。
'Who' は特に人を指すために作られた言葉だからです。名詞の繰り返しを避け、人間を説明する時に文をより簡潔にするのに役立ちます。「2階に住んでいるのはあの人だよ」は "That's the guy who lives upstairs." と言えますね。
「which」は、物、動物、考えである名詞を指し示して、2つの節をつなげます。その名詞について具体的な説明情報を加えるのに役立ちますよ。「I bought a book which was recommended.」のように使います。
物、動物、考えには常に「which」を使いましょう。人には「who」だけを使うようにしてください。「The dog who barked」のように混ぜて使うのはよくある間違いで、不自然に聞こえますよ。
「that」は主節と制限関係節をつなぎ、先行する名詞を特定するために必要な不可欠な情報を提供します。まるでピンポイントで指し示すように使えます。「This is the car that has the flat tire.」（これがパンクした車です。）
はい、もちろんです！これが「that」の大きな利点の一つです。「The person that called」（電話をかけてきた人）や「The email that arrived」（届いたメール）のように、代名詞を変えることなく使えます。
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