This is a very common question and I can totally understand why the verb 'to be' can confuse a lot of English learners. The verb 'to be' we can use in a few different situations. Let's go through each one.
Remember the verb variations:
PRESENT TENSE: IS-AM-ARE
PAST SIMPLE: WAS-WERE
PAST PARTICIPLE: BEEN
CONTINUOUS : BEING
1) BE + ADJECTIVE
The verb 'to be' we can use with an adjective to describe a noun. The noun can be ourselves or it can be something else.
It can be Something tangible-something you can touch-or intangible- something you can not touch
For example, we can say
- I am hungry
- I am tall
- She is beautiful
- They were happy
All these words underlined are adjectives, they are describing people
Other examples could be:
- The sky is blue
- My tea was cold
- Lions are dangerous
2) BE + A NOUN
We use the verb to be with a noun to describe what the noun is. As an example:
- I am a teacher
- You are a student
- This is a pen
- She was my mother
All the underlined words are nouns and we use the verb 'to be' to connect the pronouns to the nouns.
3) BE + CONTINUOUS
The continuous tense shows an action in progress for a period of time, and as you know the main verb will end -ing. Examples of this:
- I am writing
- They were walking
- We are eating
The verb 'to be' here helps to show the continuous state of the action.
In the present continuous, the structure is: IS, AM, ARE + Verb-ing
In the past continuous, the structure is: WAS, WERE + VERB-ING
4) PASSIVE VOICE
The verb 'to be' is very important in the passive voice structure and shows the tense of the action.
There are two main sentence structures:
The active voice: we focus on the subject of the sentence that does the action the structure is generally:
SUBJECT + VERB + OBJECT
- The woman drives the car
The Passive voice: we focus on the object of the sentence. they don't do any action but the action happens to them.
The structure for this is:
OBJECT + 'to be' + PAST PARTICIPLE
- The car is driven by the woman.
Note here that the object is actually called the 'Passive subject'
5) BEEN + BEING
these are different tenses- Usually 'been' will be used in the perfect tense but with the same rules and situations as above.
Likewise with 'being' this is with the passive voice in
- I am being driven to work
and with adjectives
- He's being very loud.
and this will be covered more fully in another question.
So, I hope this clears things up for you and it's a little bit clearer at least
Let me know any questions below.
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About Ajarn Ken

Ajarn Ken is an English as a second language teacher with over 10 years experience teaching English all over the world including Europe, Central and South America and Asia.
Most recently, Ken was teaching university graduates in Bangkok, Thailand English and self development to prepare them for working in the aviation industry.
Ken successfully worked with hundreds of students placing them with some of the world's most well known airlines including Qatar, Emirates, Thai Airways, Norwegian Air, Gulf Air, Singapore Airline and many more.
Ken now has his own successful and well known Instagram channel Get English Tips which has well over 100,000 followers.