Grammar Rule in 30 Seconds
Nominalization transforms adjectives into nouns to describe groups of people or abstract concepts, making your English sound more academic and sophisticated.
- Use 'The + Adjective' to describe a collective group of people (e.g., 'The unemployed').
- Add suffixes like -ness, -ity, or -ance to create abstract nouns from adjectives.
- Collective 'The + Adjective' nouns always take a plural verb form in English.
Overview
The argument was valid（その議論は妥当だった）と言う代わりに、The validity of the argument was challenged（その議論の妥当性が問われた）と言うことができます。前者は単なる状況の説明ですが、後者は「妥当性（validity）」という概念そのものを議論の主題（主語）に据えています。- 「この山は高い」（形容詞） → 「この山の高さは...」（名詞）
- 「彼は親切だ」（形容動詞） → 「彼の親切さに救われた」（名詞）
-ness, -ity, -ance などの接尾辞を用います。しかし、英語の名詞化が日本語と決定的に異なるのは、その「文構造への影響力」です。The company is resilient, which allowed it to survive the crisis. という2つの節からなる文章を、名詞化を使うと The company's resilience ensured its survival during the crisis. と1つの節にまとめることができます。ここでは resilient が resilience という「パッケージ」になり、それが主語として機能することで、文全体がより引き締まった、プロフェッショナルな印象を与えます。-ness(ゲルマン語由来)
kind→kindnessaware→awarenessdark→darkness
-ity / -ty(ラテン語由来)
active→activitycreative→creativityvalid→validityfeasible→feasibility(綴りの変化に注意)
-ance / -ence
-ant や -ent で終わる形容詞に多く見られます。important→importancesilent→silencepatient→patience
-th(古英語由来)
strong→strengthlong→lengthwide→widthdeep→depth
the+ 形容詞
the poor（貧しい人々）the elderly（高齢者）the unemployed（失業者）
- 不規則な変化
true→truthhot→heatyoung→youth
-ness | polite | politeness | His politeness was noted. | 一般的・日常的 |-ity | complex | complexity | The complexity of the task... | 学術的・抽象的 |-ence | resilient | resilience | Her resilience is amazing. | 性質としての定着 |-th | high | height | The height of the building... | 測定可能な属性 |the + Adj | rich | the rich | The rich have different problems. | 集団を指す名詞 |- Less Formal:
The system is very complex, so it is hard to use. - More Formal:
The complexity of the system hinders its usability.
Because the candidate was flexible, she was hired.The candidate's flexibility led to her recruitment.
The results were inconsistent. This inconsistency prompted further research.
inconsistency を使うことで、前の文の内容を一つの「概念」として固定し、次の議論の土台にしています。happy について論じるのではなく、happiness（幸福）という概念の定義について論じるようなケースです。the を忘れるミスが非常に多いです。特に the + adjective（集合名詞）のパターンで顕著です。- Wrong:
Poor should be supported. - Right:
The poor should be supported.
happiness, validity）は不可算名詞として冠詞をつけないのが基本ですが、特定の状況を指す場合は the が必要になります（例: The validity of this test）。この使い分けが日本人にとっての最難関です。Nounitis と呼び、文章が不自然に硬く、読みにくくなる原因となります。- Clunky:
The realization of the importance of the maintenance of the garden is necessary. - Better:
It is important to realize that we must maintain the garden.
- Wrong:
This is very importance. - Right:
This is very important./This is of great importance.
His kindness | 性質そのものを抽象的な概念として扱う。恒久的な特徴。 |Being kind | 「親切に振る舞うこと」という、一時的な行為やプロセスに焦点を当てる。 |Benevolence | より専門的、あるいは文学的な響き。日常会話ではあまり使われない。 |Kindness vs Being kindKindness is a virtue.（親切さは美徳である：一般的な概念）Being kind to others is important.（他人に親切にすることは重要だ：具体的な行為）
-ness と -ity、どちらを使えばいいか迷ったら？-able, -ible, -ic, -id などで終わるもの）なら -ity、それ以外や日常的な語なら -ness を選ぶのが安全です。ただし、reliability（信頼性）のように、例外もあります。辞書で確認する際は、その単語がどの程度のフォーマリティを持つかもチェックしましょう。The rich は単数ですか、複数ですか？The rich are... となります。もし特定の「一人の金持ち」を指したい場合は、A rich person と言う必要があります。これは the elderly, the disabled なども同様です。-ness をつければ可能ですが、実際には慣用的に使われないものもあります。例えば big を bigness と言うことは稀で、通常は size という別の名詞を使います。名詞化するよりも、より適切な既存の名詞（例: beautiful → beauty）がないか探す習慣をつけましょう。I am sorry that I was late.（遅れてすみません）よりも、I apologize for my lateness.（遅刻をお詫びします）の方が、プロフェッショナルな距離感を保つことができます。ただし、相手との関係性が近い場合は、形容詞を使った方が親しみやすさが伝わります。Common Suffixes for Nominalization
| Adjective Root | Suffix | Noun Form | Meaning/Category |
|---|---|---|---|
|
Happy
|
-ness
|
Happiness
|
State of being
|
|
Pure
|
-ity
|
Purity
|
Quality of being
|
|
Strong
|
-th
|
Strength
|
Physical quality
|
|
Silent
|
-ce
|
Silence
|
State of being
|
|
Free
|
-dom
|
Freedom
|
Condition
|
|
Wise
|
-dom
|
Wisdom
|
Abstract quality
|
|
Patient
|
-ce
|
Patience
|
Quality of being
|
|
Real
|
-ity
|
Reality
|
State of existence
|
|
Dark
|
-ness
|
Darkness
|
Physical state
|
|
Deep
|
-th
|
Depth
|
Measurement/Quality
|
Meanings
Nominalization is the process of changing an adjective into a noun. This is done either by using the definite article 'the' to refer to a group or by adding specific suffixes to create abstract nouns representing qualities or states.
Collective Nouns
Using 'the' with an adjective to represent a specific class or group of people sharing that characteristic.
“The brave often face the most danger.”
“We must support the elderly in our community.”
Abstract Qualities
Adding suffixes like -ness, -ity, or -th to an adjective to describe the concept or state of being that adjective.
“Her kindness was unexpected.”
“The complexity of the problem baffled the experts.”
Philosophical/Abstract 'The'
Using 'the' + adjective to refer to an abstract concept rather than a group of people.
“He is a seeker of the sublime.”
“The unknown is always frightening.”
Reference Table
| 形容詞 | 名詞形 | 接尾辞/変化 | 例文 |
|---|---|---|---|
|
Happy
|
Happiness
|
-ness
|
Her happiness was evident.
|
|
Creative
|
Creativity
|
-ity
|
The team's creativity was key.
|
|
Important
|
Importance
|
-ance
|
The importance of data is clear.
|
|
Silent
|
Silence
|
-ence
|
A moment of silence was observed.
|
|
Strong
|
Strength
|
-th
|
Physical strength is beneficial.
|
|
Wise
|
Wisdom
|
-dom
|
Her wisdom guided the decision.
|
|
Able
|
Ability
|
-ity
|
His ability to adapt impressed.
|
|
Dark
|
Darkness
|
-ness
|
The darkness of the night was thick.
|
|
True
|
Truth
|
Irregular change
|
We sought the truth of the matter.
|
フォーマル度スペクトル
The impoverished require substantial assistance. (Social welfare)
The poor need help. (Social welfare)
People who don't have much money need a hand. (Social welfare)
Broke folks need some love. (Social welfare)
形容詞名詞化パワーアップ
一般的な接尾辞
- happy happiness
- creative creativity
- important importance
- silent silence
- free freedom
不規則な形
- strong strength
- deep depth
- true truth
- hot heat
主な使用場面
- Formality Academic/Professional
- Abstraction Concepts/Ideas
- Conciseness Streamlined Sentences
形容詞 vs 名詞化された名詞
この形容詞は名詞化すべき？
文脈はフォーマルですか（学術的、専門的）？
その性質を抽象的な概念/主題として扱いたいですか？
この形容詞には一般的で明確な名詞形が存在しますか？
接尾辞別 形容詞名詞化
-ness
- • happiness
- • kindness
- • darkness
- • weakness
-ity/-ty
- • creativity
- • ability
- • fertile
- • cruelty
- • necessity
-ance/-ence
- • importance
- • silence
- • tolerance
- • obedience
不規則/その他
- • strength
- • depth
- • truth
- • heat
- • freedom
レベル別の例文
The rich are happy.
Her kindness is nice.
The young like to play.
I feel much happiness.
The poor need our help.
What is the length of this table?
The elderly often live alone.
His weakness is chocolate.
The unemployed are seeking new jobs.
The importance of exercise is clear.
We must respect the dead.
The beauty of the sunset was amazing.
The marginalized often lack access to healthcare.
The purity of the water is tested daily.
The brave are not those who feel no fear.
The complexity of the law is a major hurdle.
The sheer audacity of his claim was shocking.
We must bridge the gap between the privileged and the underprivileged.
The uncanny nature of the doll made me nervous.
The resilience of the economy surprised analysts.
The pursuit of the sublime often leads to isolation.
The ephemeral nature of fame is a common literary trope.
One must consider the interconnectedness of all living things.
The vulnerability of the displaced requires immediate international intervention.
間違えやすい
Learners often try to pluralize nominalized adjectives with an 's'.
Choosing which suffix to use for abstract nouns.
When to use the short form vs. the full form.
よくある間違い
The rich is happy.
The rich are happy.
He is a rich.
He is a rich man.
I have much happy.
I have much happiness.
The youngs like music.
The young like music.
The blind can't see.
Blind people can't see.
His strong is big.
His strength is great.
The importance of this is big.
The importance of this is great.
The curiousness of the child.
The curiosity of the child.
The poors are suffering.
The poor are suffering.
The silence is golden.
Silence is golden.
The complexity of the problem were high.
The complexity of the problem was high.
The disabled are fighting for rights.
People with disabilities are fighting for rights.
The depth of the water are 10 meters.
The depth of the water is 10 meters.
文型パターン
The ___ are often overlooked in society.
The ___ of the ___ is quite remarkable.
We must consider the ___ of ___ when making decisions.
He has a deep appreciation for the ___.
Real World Usage
The reliability of the data was questioned.
The unemployed march on Parliament.
I pride myself on my punctuality.
We need to do more for the marginalized.
The rights of the accused must be protected.
The durability of this phone is impressive.
フォーマルなトーンをレベルアップ
使いすぎと不自然さに注意
一般的な接尾辞を覚えよう
文脈がカギ
Smart Tips
Try to turn your main adjectives into nouns to serve as the subject of your sentences.
Use 'The + Adjective' to refer to the group as a whole, but ensure your verb is plural.
Check if the adjective is simple (like 'sad') or complex (like 'probable'). Simple words usually take '-ness'.
Use this construction sparingly for maximum impact in creative or philosophical writing.
発音
Suffix Stress Shift
When adding '-ity', the stress often shifts to the syllable immediately before the suffix.
The Schwa in Suffixes
The '-ness' suffix is usually pronounced with a reduced schwa sound /nəs/.
Vowel Change in -th
Nouns ending in '-th' often have a different vowel sound than their adjective roots.
Emphasis on the Noun
The BEAUTY of it was amazing.
Focuses the listener's attention on the abstract quality.
暗記しよう
記憶術
Remember: 'The' makes a group, 'Suffix' makes a concept. 'The rich' are many, 'Richness' is one idea.
視覚的連想
Imagine a group of people standing under a giant umbrella labeled 'THE'. Then imagine a single glowing lightbulb labeled with a suffix like '-NESS' representing a thought.
Rhyme
With 'The' it's a crowd, say it out loud. With a suffix at the end, an abstract idea is your friend.
Story
A young traveler met 'The Wise' (a group of old men). They taught him that 'Wisdom' (the abstract quality) is better than gold. He realized that 'The Greedy' (a group) would never find true 'Happiness' (the state).
Word Web
チャレンジ
Write three sentences about your country using 'The + Adjective' (e.g., The unemployed, The young) and three sentences using abstract nouns (e.g., The beauty, The importance).
文化メモ
There is a shift away from using 'the + adjective' (e.g., 'the homeless') toward 'people-first language' ('people experiencing homelessness') to emphasize humanity over condition.
British English often uses 'the + adjective' in traditional titles or social classes more frequently than American English.
In global academic English, nominalization is used to create an 'objective' voice, removing the 'I' or 'we' from research.
English nominalization stems from both Old English (Germanic) roots and Norman French/Latin influences.
会話のきっかけ
How should society support the elderly?
What is the importance of learning a second language?
In your opinion, what defines the sublime in art?
How does the resilience of a community affect its recovery from disaster?
日記のテーマ
よくある間違い
Test Yourself
The team celebrated their recent ___.
Victory は victorious の正しい最も一般的な名詞化です。Find and fix the mistake:
The accurate of his data was unquestionable.
Accuracy は accurate の正しい名詞化形です。Translate into English: 'La profundidad del océano es asombrosa.'
Answer starts with: ["T...
Depth は deep の名詞化形です。このような不規則な形には常に注意しましょう。Score: /3
練習問題
8 exercisesThe unemployed ___ struggling to find work in the current economy.
The ___ (complex) of the software makes it hard to use.
Find and fix the mistake:
The poors deserve better housing.
The way he is kind is very moving.
'The + Adjective' can be used to refer to a single person.
Match: 1. Pure, 2. Happy, 3. Strong
A: Why is he so successful? B: It's his ___. He never gives up.
Wise, Wide, Able
Score: /8
Practice Bank
11 exercisesWe discussed the ___ of the proposed changes.
Her quietness during the meeting was unusual.
Choose the correct sentence:
Translate into English: 'La conciencia ambiental es crucial para el futuro.'
Arrange these words into a sentence:
Match the adjectives with their noun forms:
The ___ of the new policy was widely debated.
The hotness of the stove was dangerous.
Choose the correct sentence:
Translate into English: 'Su sabiduría fue evidente en su consejo.'
Arrange these words into a sentence:
Score: /11
よくある質問 (8)
No, 'the young' is already plural. Adding an 's' is a common mistake.
It is always 'the rich are'. Collective adjectives take plural verbs.
Both are correct, but 'purity' is much more common and preferred in formal English.
Most can, but it's usually restricted to adjectives describing people (the old, the sick) or abstract concepts (the unknown).
'The elderly' is considered more formal and respectful in many contexts.
There is no perfect rule, but '-ness' is common for Germanic words and '-ity' for Latin-based words.
It can be, but it's more often used in philosophy to mean 'the concept of beauty'.
Yes, but it might sound a bit formal. 'His kindness' is fine, but 'The impoverished' might sound too stiff for a text.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
Lo + Adjective
English doesn't have a direct equivalent to the neuter 'lo'.
Le + Adjective
French uses masculine singular, while English collective groups are plural.
Substantivierte Adjektive
German nouns are always capitalized and have gender; English ones are not.
No / Koto
Japanese nominalization is grammatical/particle-based, not morphological (suffixes).
Masdar / Definite Adjective
Arabic nominalization is tied to the complex tri-consonantal root system.
De (的)
Chinese does not change the form of the adjective itself.
Learning Path
Prerequisites
Learn These First
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