The Past Simple is used for facts and events that existed in the past. For example:
- I was with my grandmother yesterday.
- They were at home last week.

The verb "to be" is irregular, it's past form is as follows:

I was

You were

He was

She was

It was

We were

You were

They were

Some examples of past simple sentences with the verb "to be" are:
- I was happy yesterday.
- We were teachers for 20 years.
- There was a lot of rain yesterday.
Past Simple sentences are always associated with a certain time which is either stated or implied. For example:
I was really busy yesterday. (The time is stated)
I was really busy. (The time isn't stated, but in a conversation the time would be understood.)

Past Simple negative sentences are made by adding not after the verb "to be". For example:
- It was not sunny yesterday.
- They were not in the library.

We often contract negatives, especially in spoken English:
- She was not hungry. -> She wasn't hungry.
- They were not abroad last year. -> They weren't abroad last year.

Questions are made by inverting the subject and verb. For example:
- He was a teacher.
- Was he a teacher?
- We were happy to see your family.
- Were you happy to see my family?

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