Was / Were (A1 Grammar)

Use was with I, he, she, it.

I / he / she / it: was

I was at home.
He was tired.
It was cold.
Not "I were at home." — say "I was at home.". With I, the past form is was, not were.
Try it: Yesterday it ___ very cold. (was / were / is) Answer: was — It takes was, not were. ("Is" is present, "yesterday" tells you it is past.) So: it was cold.

Use were with you, we, and they.

You were late.
We were happy.
They were at school.
Not "They was at school." — say "They were at school.". With they, use were, was is only for I, he, she, it.
Try it: Amina and Hiroshi ___ at Magaff Library. (were / was / are) Answer: were — Amina and Hiroshi = they, so the form is were, not was: They were at Magaff Library.

Before each one, ask: who? I/he/she/it → was. you/we/they → were.

He was here. / They were here.
I was tired. / We were tired.
Not "He were here. / They was here." — say "He was here. / They were here.". The subject decides: was for one (I/he/she/it), were for you/we/they.
Try it: Lars ___ at the park, but his friends ___ at the gym. (was … were / were … was / was … was) Answer: was … were — Lars = he → was. His friends = they → were. Who it is decides each one.

Add not after was or were: wasn't (I/he/she/it), weren't (you/we/they).

I wasn't hungry.
He wasn't there.
They weren't happy.
Not "I not was hungry." — say "I wasn't hungry.". The not goes after was, not before it.
Try it: She ___ at home last night. (wasn't / weren't / not was) Answer: wasn't — She takes was, so the negative is wasn't (not weren't), and not comes after: She wasn't at home.

To ask, put Was or Were before the person.

Was she at home?
Were you late?
Was it cold?
Not "You were late? (asking)" — say "Were you late?". In a question, were comes first, then the subject.
Try it: ___ you late for class? (Were / Was / Did) Answer: Were — You takes were, and in a question it comes first: Were you late? (Was is for I/he/she/it.)
Try it: Remember: who is it? Mei ___ at the cooking class. (was / were / are) Answer: was — Mei = she → was. (This is the core choice: I/he/she/it → was, you/we/they → were.)