What is the verb "to be"?
To be is the most fundamental verb in English. It is used to:
- Describe who or what someone/something is
- Give names, nationalities, jobs, and feelings
- State age, size, colour, and other qualities
- Indicate location
Unlike most verbs, to be does not describe an action — it describes a state or identity.
Form
Positive (full and contracted forms)
| Subject | Full form | Contraction |
|---|---|---|
| I | am | I'm |
| You | are | You're |
| He / She / It | is | He's / She's / It's |
| We | are | We're |
| You (plural) | are | You're |
| They | are | They're |
I'm a student.
She's from Vietnam.
They're very friendly.
Negative (full and contracted forms)
| Subject | Full form | Contraction |
|---|---|---|
| I | am not | I'm not |
| You | are not | You aren't |
| He / She / It | is not | He isn't / She isn't |
| We / They | are not | We aren't / They aren't |
I'm not tired.
He isn't a doctor.
They aren't at home.
Questions and Short Answers
| Question | Positive answer | Negative answer |
|---|---|---|
| Am I late? | Yes, you are. | No, you aren't. |
| Are you ready? | Yes, I am. | No, I'm not. |
| Is she happy? | Yes, she is. | No, she isn't. |
| Are they students? | Yes, they are. | No, they aren't. |
"Is he your brother?" "Yes, he is."
"Are you from here?" "No, I'm not. I'm from Hanoi."
Core Uses
Use 1 — Identity: names, nationality, jobs
My name is Lan.
She is Vietnamese.
He is a teacher.
They are engineers.
Use 2 — Descriptions: qualities, appearance, size, colour
The sky is blue.
This book is very interesting.
The room is small but comfortable.
Those shoes are expensive.
Use 3 — Feelings and states
I am happy today.
She is tired after work.
Are you cold? — No, I'm fine.
He is nervous about the exam.
Use 4 — Age
I am twenty years old.
How old is she? — She is thirty.
The building is over 100 years old.
Use 5 — Location (where something/someone is)
The keys are on the table.
We are in the library.
The station is near here.
Wh- Questions with "to be"
| Question word | Structure | Example |
|---|---|---|
| What | What + is/are + subject? | What is your name? |
| Who | Who + is/are + subject? | Who is that woman? |
| Where | Where + is/are + subject? | Where are the toilets? |
| How | How + is/are + subject? | How are you? |
| How old | How old + is/are + subject? | How old is your sister? |
Common Errors and How to Fix Them
| ✗ Incorrect | ✓ Correct | Why |
|---|---|---|
| She is a teacher woman. | She is a teacher. | Job uses to be + noun — no extra adjective needed |
| I am have a car. | I have a car. | have is a separate verb; never combine with am |
| He are happy. | He is happy. | He / She / It → always is |
| They is at home. | They are at home. | They → always are |
| Is it cold? Yes, it's. | Is it cold? Yes, it is. | Never contract in short affirmative answers |
Real-World Examples
Introductions:
Hi! I'm Anna. I'm from Poland. I'm a nurse.
This is my colleague, David. He's very experienced.
Descriptions:
The coffee is hot. Be careful!
These questions are really difficult.
Checking on someone:
"How are you?" "I'm great, thanks. And you?"
Talking about places:
The office is on the third floor.
Where is the nearest pharmacy?
Summary
| Use | Example |
|---|---|
| Identity / name | I'm Ana. She's a doctor. |
| Nationality / origin | He's French. They're from Brazil. |
| Description / quality | It's cold. The film is boring. |
| Feeling / state | I'm tired. Are you hungry? |
| Age | She's 25. How old is he? |
| Location | The keys are on the table. |
💡 Remember: Never contract in short positive answers:
✓ Yes, she is. — ✗ Yes, she's.