B1 · 中級 チャプター 11

Adding Extra Information and Formal Details

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

Chapter in 30 Seconds

Elevate your communication by seamlessly weaving extra details and formal precision into your English sentences.

  • Distinguish between essential and non-essential information.
  • Apply commas correctly to structure complex thoughts.
  • Master formal prepositional phrasing to sound professional.
Add detail, gain clarity, sound professional.

学べること

Want to add rich detail and clarity to your English? This chapter shows you how to smoothly include extra information using commas and master formal language, so you can express complex ideas precisely and confidently.

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 clauses to combine two short sentences into one fluid, detailed statement.
  2. 2
    By the end you will be able to: Employ formal prepositional structures in professional correspondence.

チャプターガイド

Overview

As you navigate the B1 level in English, you're moving beyond basic sentences and starting to express more nuanced and complex ideas. This chapter is your key to unlocking that next level of clarity and sophistication. We're diving into the essential skills for adding extra information and formal details, which are crucial for sounding natural and precise, especially in written English or more formal spoken contexts.
Mastering these structures will significantly enhance your ability to communicate effectively, ensuring your message is always understood exactly as you intend.
You'll learn how to seamlessly weave in additional facts and explanations without making your sentences clunky or confusing. This isn't just about sounding fancy; it's about being clear and concise, whether you're describing a person, an object, or a situation. We'll explore different types of relative clauses – the building blocks for this kind of detail – and show you how to use commas to manage the flow of information.
This includes understanding the subtle yet powerful difference between essential and non-essential information.
Furthermore, we'll equip you with the tools to handle more formal language. This is vital for academic writing, professional emails, or even just impressing an English speaker with your command of the language. By the end of this guide, your B1 English grammar will feel much more robust, allowing you to articulate complex thoughts with confidence and precision, making your English sound truly advanced.

How This Grammar Works

At the heart of adding extra information and formal details are relative clauses. These are parts of a sentence that describe a noun, giving us more specific data about it. They typically start with words like who, whom, which, that, or whose.
The critical distinction here is between defining and non-defining relative clauses.
A defining relative clause provides essential information that pinpoints *which* specific noun you're talking about. If you remove it, the meaning of the main sentence changes or becomes unclear. For instance,
The student who answered the question correctly passed the exam.
Here,
who answered the question correctly
tells us *which* student.
We don't use commas with defining clauses, and we can often use that instead of who or which.
In contrast, a non-defining relative clause adds extra, non-essential information. It's like a bonus detail. The sentence would still make sense and identify the noun without it.
These clauses are always set off by commas. For example,
My brother, who lives in London, is visiting next week.
The main point is
My brother is visiting next week.
The fact that he lives in London is just additional info. You *must* use who for people and which for things in non-defining clauses; that is never used.
For more formal contexts, especially in writing, we often place prepositions *before* the relative pronoun. Instead of saying
The colleague I spoke *to*
, formal English prefers
The colleague to whom I spoke.
Similarly,
The project *which I am working on*
becomes
The project on which I am working.
This structure elevates the formality and precision of your language.
Finally, to describe quantities within a previously mentioned group, we use relative clauses with quantifiers. These are also non-defining and use commas. We say
quantifier + of + whom/which.
For instance,
I invited ten friends to the party, all of whom accepted.
Or,
She bought three books, none of which she had read before.
This allows you to elegantly provide specific details about a subgroup, enriching your descriptions without creating separate sentences.

Common Mistakes

Learning to correctly add extra information is vital for your B1 English grammar, but it's easy to make a few common errors.
  1. 1✗ Using 'that' in non-defining clauses or forgetting commas.
✗ My car, that is red, is fast.
✓ My car, which is red, is fast.
*Explanation:* Non-defining clauses, which add extra, non-essential details, always use which (for things) or who (for people) and are separated by commas. 'That' is only for defining clauses.
  1. 1✗ Incorrectly placing prepositions in formal relative clauses.
✗ The person who I sent the email to was out of office.
✓ The person to whom I sent the email was out of office.
*Explanation:* In formal English, prepositions should precede whom (for people) or which (for things).
  1. 1✗ Not using 'of whom'/'of which' correctly with quantifiers.
✗ I have two brothers, both who live abroad.
✓ I have two brothers, both of whom live abroad.
*Explanation:* When quantifying a previously mentioned group in a non-defining clause, use
quantifier + of whom
(for people) or
quantifier + of which
(for things) after a comma.

Real Conversations

A

A

Did you enjoy the concert last night?
B

B

Yes, it was fantastic! The lead singer, who has an incredible voice, really brought the house down. And the band, which had a new drummer, sounded tighter than ever.
A

A

"I'm finalizing the report for the CEO."
B

B

Right. Did you get the figures from Sarah?
A

A

Yes. The data, all of which was verified by her department, confirms our initial projections. The CEO, to whom I will present the findings directly, expects a thorough explanation.
A

A

Have you seen John recently?
B

B

"Oh, John? My old classmate, whom I haven't seen in ages, is actually coming to my party next week. He's bringing his new dog, which I hear is a Golden Retriever."

Quick FAQ

Q

When should I use 'which' instead of 'that' when adding extra information?

You use which when the information is extra, or non-essential, and set off by commas. For example,

The new office, which is on the third floor, has great views.
If the information is essential to identify the noun, you use that (or which without commas), like
The office that is on the third floor has great views.

Q

What's the main difference between to whom and who...to?

To whom is a formal structure where the preposition comes before the relative pronoun, typically used in written English or very formal speech (e.g.,

The client to whom I sent the email
). Who...to is an informal and more common structure in everyday spoken English (e.g.,
The client who I sent the email to
). Both are grammatically correct but convey different levels of formality.

Q

Can I use all of that or none of that instead of all of which or none of which?

While all of that or none of that can be used in some contexts, particularly informally, when referring back to a *previously mentioned noun or clause* as part of a non-defining relative clause, you should use

all of which
or
none of which.
For example,
She mentioned several problems, all of which need attention.

Q

Why are commas so important when adding extra information with relative clauses?

Commas are crucial because they signal whether the information is essential or non-essential. Using them correctly prevents misunderstandings and makes your writing clearer. Incorrect comma usage can completely change the meaning or make a sentence ungrammatical.

Cultural Context

Native English speakers use these patterns constantly, though often unconsciously. The more formal structures (like prepositions before whom/which and quantifiers) are far more common in written English – reports, academic papers, formal emails – than in casual conversation. In daily speech, speakers tend to opt for simpler, less formal constructions like splitting the preposition from the relative pronoun or rephrasing entirely.
Understanding this distinction helps you sound natural whether you're chatting with a friend or writing a professional document.

重要な例文 (8)

1

The profile that has the blue checkmark is the real one.

青いチェックマークがあるプロフィールが本物です。

関係代名詞：制限用法と非制限用法の意味の違い
2

My laptop, which I bought only last month, is already lagging.

私のノートパソコン、先月買ったばかりなのに、もう動作が遅いんです。

関係代名詞：制限用法と非制限用法の意味の違い
3

My brother, who lives in Sydney, is a fantastic surfer.

私の兄は、シドニーに住んでいますが、素晴らしいサーファーです。

非限定関係節：追加情報（コンマ付き）
4

The new restaurant, which opened last week, serves delicious vegan options.

先週オープンしたばかりの新しいレストランは、美味しいヴィーガン料理を提供しています。

非限定関係節：追加情報（コンマ付き）
5

The professor, to whom I submitted my thesis, provided invaluable feedback.

私が論文を提出した教授は、非常に貴重なフィードバックをくれました。

関係代名詞における前置詞の公式な使い方 (to whom, for which)
6

This is the complex issue for which a solution is urgently needed.

これは、早急な解決策が求められている複雑な問題です。

関係代名詞における前置詞の公式な使い方 (to whom, for which)
7

I have three brothers, all of whom are engineers.

私は3人の兄弟がいて、全員エンジニアです。

数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)
8

He sent me ten emails, none of which I have read yet.

彼は私に10通のメールを送ってきたけど、まだどれも読んでいません。

数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)

ヒントとコツ (4)

🎯

指差しトリック

もし「あれだよ！」って指差して特定できるなら、それは限定用法です。カンマは必要ありません。「The book that I read...」
frontend.learn_grammar.from_rule: 関係代名詞：制限用法と非制限用法の意味の違い
💡

コンマが「道しるべ」

コンマは「この情報はなくても大丈夫だよ」というサインです。その部分をなくしても文が成り立つなら、コンマが必要です。
If you remove the clause, the main sentence still makes sense.
frontend.learn_grammar.from_rule: 非限定関係節：追加情報（コンマ付き）
💡

Whom を使うタイミング

代名詞を 'him' や 'her' に置き換えられる場合は 'whom' を使います。 'to him' なら 'to whom' という感じですね。
The person to whom I gave the gift.
frontend.learn_grammar.from_rule: 関係代名詞における前置詞の公式な使い方 (to whom, for which)
⚠️

カンマは本当に大切！

量化詞の前のカンマは絶対に省かないでくださいね。これは「補足情報だよ」という合図で、文が長くなりすぎるのを防ぎます。「The sentence becomes a 'run-on' and is much harder to read.」
frontend.learn_grammar.from_rule: 数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)

重要な語彙 (5)

clause a part of a sentence containing a verb define to explain the nature or meaning of something formal appropriate for official or serious situations quantifier a word expressing amount, like all or none preposition a word showing relationship like to, for, or with

Real-World Preview

users

Professional Introduction

Review Summary

  • Noun + that/who + verb
  • Noun, + which/who + verb, + rest
  • Prep + whom/which
  • Quantifier + of + whom/which

よくある間違い

You don't need 'he' if 'who' already acts as the subject. The extra 'he' is redundant.

Wrong: My brother, who lives in Paris, he is a chef.
正解: My brother, who lives in Paris, is a chef.

When using a formal structure, the preposition moves to the front, and the object pronoun is removed.

Wrong: The person that I spoke to him was nice.
正解: The person to whom I spoke was nice.

Use 'which' or 'whom' to connect the clause to the main sentence, not 'them'.

Wrong: I have many books, all of them are new.
正解: I have many books, all of which are new.

Next Steps

You've unlocked a higher level of English precision! Keep practicing, and don't be afraid to use these structures in your daily writing.

Write a formal email to a professor describing your research interests.

Continue to: Mastering Ability and Polite Requests

クイック練習 (10)

フォーマルな文の中にある間違いを見つけて直してください。

Find and fix the mistake:

This is the objective to who we are striving.

✓ Correct! ✗ Not quite. Correct answer: This is the objective to which we are striving.
objective（目標）は「物・事」なので、whom ではなく which を使います。

frontend.learn_grammar.from_rule: 関係代名詞における前置詞の公式な使い方 (to whom, for which)

フォーマルな関係代名詞の構造を正しく使っている文はどれですか？

正しい文を選んでください：

✓ Correct! ✗ Not quite. Correct answer: The regulations, about which they complained, were difficult.
フォーマルな形では、物に対して前置詞 ＋ which を使います。that は使いません。

frontend.learn_grammar.from_rule: 関係代名詞における前置詞の公式な使い方 (to whom, for which)

文の中の間違いを見つけて直しましょう。

Find and fix the mistake:

I have many unread notifications, some of who are from Instagram.

✓ Correct! ✗ Not quite. Correct answer: some of which are from Instagram.
通知は物なので、「who」ではなく「which」を使わなければなりません。

frontend.learn_grammar.from_rule: 数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)

文法的に正しい文を選びましょう。

Choose the best sentence for a formal essay:

✓ Correct! ✗ Not quite. Correct answer: She wrote five books, all of which are famous.
この文は、「which」（本について）と必要なカンマを正しく使っています。

frontend.learn_grammar.from_rule: 数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)

特定の、すでに知られている人物についてのこの文の間違いを見つけてください。

Find and fix the mistake:

Mr. Smith that is my teacher is very kind.

✓ Correct! ✗ Not quite. Correct answer: Mr. Smith, who is my teacher, is very kind.
彼の名前が分かっているので、情報は追加的なものです。カンマと「that」の代わりに「who」が必要です。

frontend.learn_grammar.from_rule: 関係代名詞：制限用法と非制限用法の意味の違い

文の間違いを見つけて修正しましょう。

Find and fix the mistake:

The new cafe that has a rooftop terrace is very popular.

✓ Correct! ✗ Not quite. Correct answer: The new cafe, which has a rooftop terrace, is very popular.
「has a rooftop terrace」という節は、「the new cafe」（「the new」で十分に特定されている）についての必須ではない追加情報です。そのため、コンマで区切る必要があり、非制限用法では「that」の代わりに「which」を使わなければなりません。

frontend.learn_grammar.from_rule: 非限定関係節：追加情報（コンマ付き）

正しい関係代名詞と句読点を選びましょう。

My best friend ___ is a brilliant artist, just had her first exhibition.

✓ Correct! ✗ Not quite. Correct answer: , who
「my best friend」はすでに特定されているので、「is a brilliant artist」という節は追加の、必須ではない情報です。そのため、コンマで区切る必要があり、人に対しては「who」を使います。

frontend.learn_grammar.from_rule: 非限定関係節：追加情報（コンマ付き）

正しい関係代名詞を埋めましょう。

I have two best friends, both of ___ live in London.

✓ Correct! ✗ Not quite. Correct answer: whom
人（友達）について話しているので、「whom」を使います。

frontend.learn_grammar.from_rule: 数・量を表す言葉を伴う関係代名詞 (all of whom, none of which)

「that」か「which」で空欄を埋めてください。カンマのルールを思い出してね！

Tokyo, ___ is the capital of Japan, is a huge city.

✓ Correct! ✗ Not quite. Correct answer: which
これは非限定用法（唯一の場所に関する追加情報）なので、「that」ではなく「which」を使わなければなりません。

frontend.learn_grammar.from_rule: 関係代名詞：制限用法と非制限用法の意味の違い

フォーマルな文を完成させるために、正しい形を選んでください。

The candidate, _____ the committee voted unanimously, accepted the position.

✓ Correct! ✗ Not quite. Correct answer: for whom
候補者（人）であり、前置詞 for が前に来ているので、フォーマルな 'whom' が正解です。

frontend.learn_grammar.from_rule: 関係代名詞における前置詞の公式な使い方 (to whom, for which)

Score: /10

よくある質問 (6)

限定用法は、どの人や物について話しているのかを特定するのに使います（これは必須情報）。非限定用法は、もう分かっていることに追加情報を与えるだけです（おまけ情報）。例えば、「The car that I bought」は「私が買った、その車」と特定するけど、「My car, which I bought last month,」は「私の車（もう特定されてるよね）、先月買ったんだけどね」って感じだよ。
非限定用法の場合には、常にカンマを使います。カンマは追加情報を「かっこ」で囲むような役割をしてくれます。「My brother, who lives in London, is a doctor.」
すでに特定されている名詞について、余分な、つまり「なくても意味は通じる」追加情報を付け加えることです。話している人やモノを特定するのに必須ではない、「おまけ」や「ちょっとした補足」のようなものだと思ってください。
一番簡単な見分け方は、コンマがあるかどうかです！非制限用法は必ずコンマで区切られています。また、その部分を文から取り除いてみて、元の文が完全に意味をなすなら、それは非制限用法です。
who は主語（he/she のよう）として使い、whom は目的語（him/her のよう）として使います。前置詞が前に来る場合は必ず whom になります。 to whom
より正確で洗練された印象を与えられるからです。論文やビジネス、目上の人と話す時に信頼感が増しますよ。
the report for which I was responsible
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