Grammar Rule in 30 Seconds
Use 'likely' and 'unlikely' to express probability with more precision and formality than 'maybe' or 'probably'.
- Use 'Subject + be + likely + to + verb' for personal predictions: 'He is likely to win.'
- Use 'It + be + likely + that + clause' for general situations: 'It is likely that prices will rise.'
- Modify with 'highly', 'more than', or 'very' to adjust the strength of the prediction.
Overview
It is likely that the price will go up と言います。こうすれば、もし価格が下がっても、あなたは嘘つきではなく、単に「可能性」を議論していただけということになります。C1レベルでは、maybe や probably といった単純な言葉を卒業する必要があります。これらはピザの注文についてルームメイトにLINEする分にはいいですが、論文を書いたり契約の交渉をしたりする場面では不十分です。It is likely/unlikely that を使うことは、あなたが「確実性」の微妙なニュアンスを理解していることを示します。よりプロフェッショナルで、思慮深く、そして正直なところ、人生が100%確実であることは滅多にないと知っているネイティブスピーカーのように聞こえます。文の形をした「プロフェッショナルな肩すかし」だと考えてください。How This Grammar Works
likely（または unlikely）という単語に基づいています。よくある罠は、-ly で終わるから likely を副詞だと思ってしまうことですが、これらの特定の構造では、状況全体の可能性を説明しています。これらの文を作るには主に2つの方法があります。1つ目は「形式主語のit」構造：It is likely that [何かかが起こる] です。これは出来事そのものに焦点を当てるため、非常に優れています。客観的です。データを見て論理的な結論に達したように聞こえます。2つ目は「人称主語」構造：He is likely to [何かをする] です。こちらは少し直接的な感じがし、話し言葉で非常によく使われます。例えば、Netflixのドラマを見ていて、登場人物が一人で暗い地下室に入っていくのを見たとき、友達に It is highly unlikely that they survive this episode（このエピソードで彼らが生き残る可能性は極めて低い）とささやくかもしれません。あるいは、もっと直接的に They are unlikely to survive と言うこともできます。どちらもC1レベルとして素晴らしいですが、It is... that バージョンは学術的・フォーマルなライティングにおける最高の味方です。フォーマルな英語が好む、少し突き放したような客観性を保つことができます。
Formation Pattern
It から始めます。
to be 動詞を加えます（通常は is ですが、was や will be の場合もあります）。
likely または unlikely を入れます。
that を加えます。
It + is + likely + that + the event will be sold out.
Subject（主語）から始めます。
to be 動詞を加えます（主語に合わせて活用させます）。
likely または unlikely を加えます。
to-infinitive（不定詞）の形を加えます。
The tickets + are + unlikely + to be available.
likely/unlikely の前に副詞を置いて文を強化できます。
highly, very, extremely, most などを使って強調します。
It is highly likely that your cat is judging you right now（今、あなたの猫があなたを品定めしている可能性は極めて高いです）。
When To Use It
It is unlikely that the project will meet the deadline（プロジェクトが期限に間に合う可能性は低いです）と言えば、リスクを特定できる戦略的な天才のように聞こえます。すべては「ソフトランディング」のためです。ニュース記事や学術論文でも絶えず目にすることでしょう。ジャーナリストが It is likely that を好むのは、予測が外れたときに訴訟から身を守れるからです。プライベートでは、旅行の計画やバズっているトレンドについて使ってみてください。「TikTokは禁止されるの？」→ It's unlikely that it will happen overnight（一晩で起こる可能性は低いよ）。また、「丁寧な反対意見」を述べる際にも完璧なツールです。友達がトレーニングもせずにマラソンを完走できると思っているなら、It's unlikely that you'll finish without a few blisters（靴ずれの一つもなしに完走できる可能性は低いね）と言えば、「絶対に無理だよ」と言うよりもずっと印象が良くなります。これは「現実的な楽観主義者」の文法です。最善を望みつつも、データがそうでないと言う場合に備えているのです。
Common Mistakes
It is... の構造では、必ず that の後に完全な文（節）を続けなければなりません。「him」を使いたいなら、もう一つの構造 He is likely to win に切り替える必要があります。また、to be 動詞を完全に忘れてしまうのもよくあるミスです。「It likely that...」は壊れたロボットのように聞こえます。is を忘れないでください。さらに、probably という単語にも注意が必要です。likely と probably は似た意味ですが、文法は全く違います。「I will probably go」とは言えますが、標準的なイギリス英語では「I will likely go」とは言えません（アメリカ人はよく言いますが）。フォーマルな試験では、likely は to be 動詞を必要とする形容詞として扱ってください。最後に、ヘッジをしすぎないこと！ It is possibly likely that maybe... などと言うと、自信喪失に陥っているように聞こえます。可能性のレベルを一つ選んで、それに固執しましょう。Contrast With Similar Patterns
will や is bound to を使います。90%確信があるなら、It is likely that を使います。50%なら、It is possible that や might になります。Likely は可能性の「スイートスポット（最適点）」です。possible より強いですが、certain よりは柔らかい。probably と比較すると、likely は単なる直感ではなく、外部の根拠に基づいているように感じられます。「I’ll probably be late」と言うと、単に時間にルーズな人に聞こえますが、It is likely that I will be late と言うと、Googleマップで分析した結果、大渋滞が発生しているように聞こえます。また、予定や約束のために起こる「はず」のことには It is expected that が使われますが、likely は純粋に確率の話です。likely/unlikely を使うことで、単純な助動詞 could や may には欠けがちな、洗練された分析的な響きを英語に与えることができます。Quick FAQ
「It is more likely that」と言えますか？
もちろんです！比較に最適です。It is more likely that I’ll stay in than go to the club（クラブに行くより家にいる可能性の方が高いね）。
「It is unlikely that」は「I doubt that」と同じですか？
とても似ていますが、I doubt that はより個人的で主観的です。It is unlikely that はより客観的な事実に聞こえます。レポートやプレゼンでは後者を使いましょう。
常に 「that」 は必要ですか？
フォーマルなライティングではイエスです。カジュアルなチャットでは省略されることも多いですが（It's likely he'll call later）、C1レベルの試験では that を入れておきましょう！
過去形で使えますか？
はい！ It was unlikely that the team would win, but they did（チームが勝つ可能性は低かったが、彼らは勝った）。他の動詞も過去にずらすのを忘れないでください。
「highly likely」と「very likely」の違いは何ですか？
highly likely の方が少しフォーマルで、より「C1レベル」らしく聞こえます。パーカーを着るかブレザーを着るかの違いのようなものです。どちらも正解ですが、一方がよりフォーマルです。
Forming Predictions with 'Likely'
| Subject | Verb 'to be' | Likelihood | Infinitive/Clause |
|---|---|---|---|
|
I
|
am
|
likely
|
to attend
|
|
You
|
are
|
unlikely
|
to fail
|
|
It
|
is
|
highly likely
|
that it will rain
|
|
We
|
are
|
more than likely
|
to win
|
|
They
|
were
|
unlikely
|
to have known
|
|
The results
|
are
|
likely
|
to be significant
|
Common Contractions
| Full Form | Contracted Form |
|---|---|
|
It is likely
|
It's likely
|
|
They are unlikely
|
They're unlikely
|
|
I am not likely
|
I'm not likely
|
Meanings
The words 'likely' and 'unlikely' function as adjectives in English to indicate the probability of an event occurring. They are essential for 'hedging'—the practice of making cautious or vague statements to avoid over-generalization.
Predictive Adjective
Used to describe the probability of a future action or state.
“A recession is likely in the coming months.”
“It is unlikely that the team will recover from this loss.”
Academic Hedging
Used in research and formal reports to present findings as probable rather than absolute truths.
“The data suggests that these results are likely to be replicated.”
“It is highly unlikely that the variables are unrelated.”
Adverbial Usage (US English)
In American English, 'likely' is often used as an adverb meaning 'probably'.
“They'll likely arrive around six.”
“He will most likely decline the offer.”
Reference Table
| Form | Structure | Example |
|---|---|---|
|
Affirmative (Personal)
|
Subj + be + likely + to + verb
|
She is likely to call later.
|
|
Affirmative (Impersonal)
|
It + be + likely + that + clause
|
It is likely that she will call.
|
|
Negative (Adjective)
|
Subj + be + unlikely + to + verb
|
They are unlikely to arrive on time.
|
|
Negative (Verb)
|
Subj + be + not + likely + to + verb
|
They are not likely to arrive on time.
|
|
Question
|
Be + Subj + likely + to + verb?
|
Are you likely to be home by six?
|
|
Modified
|
Subj + be + highly likely + to + verb
|
The price is highly likely to rise.
|
フォーマル度スペクトル
It is highly likely that I shall be delayed. (Professional vs. Casual communication)
I am likely to be late. (Professional vs. Casual communication)
I'll likely be late. (Professional vs. Casual communication)
Prob gonna be late. (Professional vs. Casual communication)
The Probability Scale
High Probability
- Highly likely 90% chance
- More than likely 80% chance
Low Probability
- Unlikely 20% chance
- Highly unlikely 5% chance
Likely vs. Probably
Choosing Your Structure
Are you focusing on a person/thing?
レベル別の例文
It is likely.
It is likely.
Is it likely?
Is it likely?
It is unlikely.
It is unlikely.
Very likely.
Very likely.
The train is likely to be late.
The train is likely to be late.
It is likely that he is at home.
It is likely that he is at home.
She is unlikely to come to the party.
She is unlikely to come to the party.
Are you likely to finish today?
Are you likely to finish today?
We are likely to see more rain this week.
We are likely to see more rain this week.
It's unlikely that they will change their minds.
It's unlikely that they will change their minds.
Is it likely to cost a lot of money?
Is it likely to cost a lot of money?
He is not likely to win the race.
He is not likely to win the race.
The government is likely to introduce new taxes.
The government is likely to introduce new taxes.
It is highly unlikely that the error was accidental.
It is highly unlikely that the error was accidental.
They are more than likely to accept the offer.
They are more than likely to accept the offer.
The project is unlikely to be completed on time.
The project is unlikely to be completed on time.
Such a scenario is highly likely to provoke a strong reaction.
Such a scenario is highly likely to provoke a strong reaction.
It is increasingly likely that the policy will be reversed.
It is increasingly likely that the policy will be reversed.
The findings are unlikely to have a significant impact on the field.
The findings are unlikely to have a significant impact on the field.
Is it not likely that the witness was mistaken?
Is it not likely that the witness was mistaken?
In all likelihood, the merger will proceed as planned.
In all likelihood, the merger will proceed as planned.
The candidate is singularly unlikely to garner enough support.
The candidate is singularly unlikely to garner enough support.
It remains highly likely that further interventions will be required.
It remains highly likely that further interventions will be required.
Were the results to be skewed, a re-evaluation would be likely.
Were the results to be skewed, a re-evaluation would be likely.
間違えやすい
Learners use 'likely' as an adverb without a modifier, which sounds unnatural in some dialects.
Both can mean 'probable', but 'liable' often implies a negative or legal responsibility.
Learners use 'likely' when they are 100% certain.
よくある間違い
I likely go.
I will probably go.
It likely.
It is likely.
Is likely?
Is it likely?
Very likely rain.
It is very likely to rain.
He is likely go.
He is likely to go.
It is likely that rain.
It is likely that it will rain.
I am unlikely for come.
I am unlikely to come.
He will likely to win.
He is likely to win.
It is likely him to win.
He is likely to win.
The likely result is it wins.
The likely result is that it will win.
He likely won't come.
He is unlikely to come.
It is likely that he comes tomorrow.
It is likely that he will come tomorrow.
The highly likelyhood of success.
The high likelihood of success.
It is unlikely for there to be a problem.
It is unlikely that there will be a problem.
文型パターン
Subject + be + likely + to + ___
It + is + ___ + likely + that + ___
___ + is + unlikely + to + ___
In all likelihood, ___
Real World Usage
Showers are likely in the afternoon.
We are likely to exceed our targets this quarter.
The treatment is likely to cause some fatigue.
They are unlikely to make a comeback at this stage.
It is likely that the results were influenced by sample size.
I'm likely to be a bit late, don't wait up!
Use 'Highly' for Impact
Watch the 'To'
The British Understatement
Impersonal vs Personal
Smart Tips
Switch from 'I think it will...' to 'It is likely that...'.
Use the 'Subject + be likely to' structure to keep the focus on the person.
Use 'more than likely' instead of just 'likely'.
Remember that 'Is it unlikely...?' is asking if something is NOT going to happen.
発音
Likely
Two syllables. Stress on the first syllable.
Unlikely
Three syllables. Stress on the second syllable.
Rising-Falling on 'Likely'
He is LIKELY to win. ↘
Conveys a confident prediction.
暗記しよう
記憶術
L-I-K-E-L-Y: Look Into Known Evidence, Logically Yielding (a prediction).
視覚的連想
Imagine a weather vane pointing towards a rain cloud. The vane represents 'likely'—it's not raining yet, but the evidence (the wind) suggests it will.
Rhyme
If it's likely to be, it's a future we see; if it's unlikely to occur, the vision is a blur.
Story
A cautious scientist named Dr. Hedge never says 'will'. When asked if the volcano will erupt, he says, 'It is likely to erupt, but it is unlikely to happen today.' He keeps his job because he is never wrong, just 'likely' right.
Word Web
チャレンジ
Write three predictions for your life in five years using 'likely to', 'unlikely to', and 'highly likely that'.
文化メモ
British speakers are very fond of hedging to avoid appearing too direct or aggressive. Using 'likely' is a key part of polite, professional disagreement.
In the US, 'likely' is frequently used as an adverb (e.g., 'He likely forgot'). This is less common in formal British English.
In global academic culture, using 'likely' is a sign of intellectual humility and scientific rigor.
From Middle English 'likly', meaning 'having the appearance of being true'.
会話のきっかけ
What are you likely to do this weekend?
Is it likely that AI will replace most jobs in the next decade?
Which team is likely to win the next World Cup?
In your opinion, is it likely that we will discover life on other planets soon?
日記のテーマ
よくある間違い
Test Yourself
The prices are ___ to rise next month.
Which sentence is correct?
Find and fix the mistake:
She likely to win the race.
I don't think it will rain.
Match each item on the left with its pair on the right:
A: Do you think they'll accept the offer? B: It's ___.
Identify the adjective:
likely / is / to / the / be / late / flight
Score: /8
練習問題
8 exercisesThe prices are ___ to rise next month.
Which sentence is correct?
Find and fix the mistake:
She likely to win the race.
I don't think it will rain.
Match the following:
A: Do you think they'll accept the offer? B: It's ___.
Identify the adjective:
likely / is / to / the / be / late / flight
Score: /8
Practice Bank
11 exercisesThe new game update is ___ to fix many of the existing bugs.
He likely will be late because of traffic.
Which sentence uses 'unlikely' correctly?
Translate into English: 'Es muy probable que llueva mañana.'
Arrange these words into a sentence:
Match the sentence beginnings with appropriate endings:
The concert tickets are selling fast, so it's ___ that they'll be available much longer.
Our professor likely will give us an extension.
Select the correct sentence:
Translate: 'Es improbable que lo terminemos a tiempo.'
Put the words in the right order:
Score: /11
よくある質問 (8)
Yes, especially in American English (e.g., 'He likely forgot'). However, in formal British English, it is better to use it as an adjective ('He is likely to have forgotten') or add a modifier ('He very likely forgot').
'Unlikely' is an adjective that feels a bit more formal and direct. 'Not likely' is simply the negation of the adjective 'likely'. Both are common, but 'unlikely' is preferred in academic writing.
Usually, yes. Since you are making a prediction, the 'that' clause needs a future marker like `will` or `is going to`. Example: `It is likely that he will win.`
Yes, 'likely' is generally considered more formal and objective, making it the preferred choice for reports, news, and academic papers.
Absolutely. 'Most likely' is a very common way to say 'almost certainly'. It can be used as an adverbial phrase: 'Most likely, we will stay home.'
This is a formal idiom that means 'almost certainly' or 'very probably'. It is a great phrase to use at the start of a sentence in C1-level writing.
Yes, by using the perfect infinitive: 'He is likely to have arrived by now.' This means it is probable that he arrived in the past.
Yes, it has a negative meaning (low probability), but it is grammatically affirmative. You don't need to add 'not' to 'unlikely'.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
Es probable que + subjunctive
Spanish requires the subjunctive mood.
Il est probable que + indicative/subjunctive
Nuance between probability and possibility affects mood.
Wahrscheinlich / Voraussichtlich
German prefers adverbs over the 'be likely to' adjective structure.
〜そうだ (sou da) / 〜らしい (rashii)
Japanese uses grammatical particles and suffixes rather than a 'to be' adjective structure.
من المحتمل أن (min al-muhtamal an)
Arabic uses a prepositional phrase structure.
很可能 (hěn kěnéng)
Chinese lacks the complex infinitive/clause distinction found in English.
Learning Path
Prerequisites
Learn These First
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06:52 What happens to your brain without any social contact? - Terry Kupers
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