Be-verbs are one of the most important parts of English grammar. They come from the verb to be, which is used to describe identity, state, condition, location, and existence. Unlike most verbs, be-verbs do not always show an action. Instead, they often link the subject to more information about the subject.
1. Forms of the Be-Verb
The verb to be has several forms depending on tense (time) and subject (who or what the sentence is about).
Present tense
- am → used with I
- is → used with he, she, it
- are → used with you, we, they
Examples:
- I am a teacher.
- She is happy.
- They are students.
Past tense
- was → used with I, he, she, it
- were → used with you, we, they
Examples:
- I was tired yesterday.
- We were at the park.
Other forms
- be (base form) → used after modal verbs (can, will, should)
- being (present participle) → used in continuous forms
- been (past participle) → used in perfect tenses
Examples:
- She will be late.
- He is being noisy.
- They have been busy.
2. Main Uses of Be-Verbs
A. To describe identity (who someone is)
Be-verbs connect the subject to a noun that tells us what the subject is.
Examples:
- He is a doctor.
- I am a student.
- They are my friends.
Here, the be-verb links the subject to its identity.
B. To describe condition or state
Be-verbs are often used with adjectives.
Examples:
- She is happy.
- The water is cold.
- I am tired.
There is no action here. The verb simply describes a condition.
C. To describe location
Be-verbs show where someone or something is.
Examples:
- The book is on the table.
- We are in Japan.
- He was at home.
D. To describe age, time, and weather
In English, we use be-verbs for many common expressions.
Examples:
- I am 15 years old.
- It is 3 o’clock.
- It is sunny today.
E. To show existence (There is / There are)
Be-verbs are used with “there” to say something exists.
Examples:
- There is a cat in the room.
- There are two cars outside.
3. Be-Verbs as Helping Verbs (Auxiliary Verbs)
Be-verbs are also used as helping verbs to form other tenses.
A. Continuous (Progressive) Tense
Be + verb(-ing) shows an action happening now or around now.
Examples:
- I am studying English.
- She is running.
- They are watching TV.
B. Passive Voice
Be + past participle shows that the subject receives the action.
Examples:
- The book is written in English.
- The cake was made by my mother.
4. Negative Sentences with Be-Verbs
To make a negative sentence, add not after the be-verb.
Examples:
- I am not ready.
- She is not here.
- They are not tired.
Short forms (contractions):
- am not → (no contraction for “I am not” → sometimes “I’m not”)
- is not → isn’t
- are not → aren’t
5. Questions with Be-Verbs
To make a question, move the be-verb to the front of the sentence.
Examples:
- Are you ready?
- Is she your teacher?
- Were they at school?
Short answers:
- Yes, I am. / No, I am not.
- Yes, she is. / No, she isn’t.
6. Common Mistakes
Mistake 1: Forgetting the be-verb
❌ She happy.
✅ She is happy.
Mistake 2: Using the wrong form
❌ I is a student.
✅ I am a student.
Mistake 3: Confusing be-verbs with action verbs
❌ I am go to school.
✅ I go to school.
✅ I am going to school.
7. Be-Verbs vs Action Verbs
Be-verbs describe a state, while action verbs show action.
Examples:
- She is tired. (state)
- She runs every day. (action)
Sometimes they work together:
- She is running. (be-verb + action verb)
8. Why Be-Verbs Are Important
Be-verbs are used in:
- Basic sentences
- Descriptions
- Questions
- Continuous tenses
- Passive voice
Without be-verbs, many English sentences would be incomplete or incorrect.
9. Summary
Be-verbs come from the verb to be and include:
- am, is, are, was, were, be, being, been
They are used to:
- Describe identity → She is a teacher.
- Describe condition → He is tired.
- Show location → They are at home.
- Form continuous tenses → I am studying.
- Form passive voice → The book was written.
Final Tip
If you are not sure which be-verb to use, ask yourself:
- Who is the subject? (I, you, he, they, etc.)
- When is the action? (present or past)
Then choose the correct form.
be動詞は英語文法の中で最も重要な要素の一つです。動詞 to be（〜である） から来ており、人や物の正体・状態・場所・存在などを表します。一般の動詞のように「動作」を表すのではなく、主語とその説明をつなぐ役割を持っています。
1. be動詞の形
be動詞は、時制（時間）と主語によって形が変わります。
現在形
- am → I と一緒に使う
- is → he, she, it と一緒に使う
- are → you, we, they と一緒に使う
例：
- I am a teacher.（私は先生です）
- She is happy.（彼女は幸せです）
- They are students.（彼らは学生です）
過去形
- was → I, he, she, it
- were → you, we, they
例：
- I was tired yesterday.（昨日は疲れていました）
- We were at the park.（私たちは公園にいました）
その他の形
- be（原形）→ 助動詞の後で使う
- being（現在分詞）→ 進行形で使う
- been（過去分詞）→ 完了形で使う
例：
- She will be late.（彼女は遅れるでしょう）
- He is being noisy.（彼は騒いでいます）
- They have been busy.（彼らは忙しかったです）
2. be動詞の主な使い方
A. 正体（何者か）を表す
主語が「何であるか」を説明します。
例：
- He is a doctor.（彼は医者です）
- I am a student.（私は学生です）
- They are my friends.（彼らは私の友達です）
B. 状態・様子を表す
形容詞と一緒に使って状態を表します。
例：
- She is happy.（彼女は幸せです）
- The water is cold.（水は冷たいです）
- I am tired.（私は疲れています）
C. 場所を表す
人や物がどこにあるかを示します。
例：
- The book is on the table.（本は机の上にあります）
- We are in Japan.（私たちは日本にいます）
- He was at home.（彼は家にいました）
D. 年齢・時間・天気を表す
英語ではこれらもbe動詞で表します。
例：
- I am 15 years old.（私は15歳です）
- It is 3 o’clock.（3時です）
- It is sunny today.（今日は晴れです）
E. 存在を表す（There is / There are）
「〜がある／いる」という意味です。
例：
- There is a cat in the room.（部屋に猫がいます）
- There are two cars outside.（外に車が2台あります）
3. 助動詞としてのbe動詞
be動詞は**助動詞（補助動詞）**としても使われます。
A. 進行形
be動詞 + 動詞のing形で「〜している」を表します。
例：
- I am studying English.（英語を勉強しています）
- She is running.（彼女は走っています）
- They are watching TV.（テレビを見ています）
B. 受動態
be動詞 + 過去分詞で「〜される」を表します。
例：
- The book is written in English.（その本は英語で書かれています）
- The cake was made by my mother.（そのケーキは母によって作られました）
4. 否定文
be動詞の後に not を置きます。
例：
- I am not ready.（準備ができていません）
- She is not here.（彼女はここにいません）
- They are not tired.（彼らは疲れていません）
短縮形：
- is not → isn’t
- are not → aren’t
5. 疑問文
be動詞を文の先頭に出します。
例：
- Are you ready?（準備はいいですか？）
- Is she your teacher?（彼女はあなたの先生ですか？）
- Were they at school?（彼らは学校にいましたか？）
短い答え：
- Yes, I am. / No, I am not.
- Yes, she is. / No, she isn’t.
6. よくある間違い
間違い1：be動詞を忘れる
❌ She happy.
✅ She is happy.
間違い2：形を間違える
❌ I is a student.
✅ I am a student.
間違い3：一般動詞と混同する
❌ I am go to school.
✅ I go to school.
✅ I am going to school.
7. be動詞と一般動詞の違い
- be動詞 → 状態を表す
- 一般動詞 → 動作を表す
例：
- She is tired.（状態）
- She runs every day.（動作）
組み合わせ：
- She is running.（走っている）
8. なぜbe動詞が重要か
be動詞は次のような場面で使われます：
- 基本文
- 説明
- 疑問文
- 進行形
- 受動態
be動詞がないと、多くの英語の文は不完全になります。
9. まとめ
be動詞には次の形があります：
- am, is, are, was, were, be, being, been
使い方：
- 正体 → She is a teacher.
- 状態 → He is tired.
- 場所 → They are at home.
- 進行形 → I am studying.
- 受動態 → The book was written.
最後のポイント
どのbe動詞を使うか迷ったら：
- 主語は何か？（I, you, he, they など）
- 時制はいつか？（現在か過去か）
この2つを考えれば、正しい形を選ぶことができます。
