This tense is used to represent the action or an object or a human being or a person we perceived before us in the past time.

I, WE, YOU, THEY, HE, SHE, IT are the subjects in a sentence.

In those sentences with I, WE, YOU, or THEY as a subject WAS, WERE, or HAD are the auxiliaries are used to denote past tense.

WAS is used to denote past tense with the subjects such as I, HE, and SHE as they are used to denote singular form of subjects.

WERE is used to denote past tense with the subjects such as WE, YOU, and THEY as they are used to denote plural forms of subjects.

HAD is used with all the subjects to denote the past tense in common. HAD is used in a sentence with a subject to express a possession of a character or a quality or a thing.

Examples:

1. He HAD two costly cars with him last year.
2. She HAD a bad habit of nail-biting once upon a time, but she abstained from that now.
3. They HAD no good qualities to win the competition.

See some examples used in question and answers:

1. Where WERE you yesterday?

I WAS in my grandma's house yesterday.

2. What WAS the age limit for civil services examinations in 1980 for an upper caste candidate?

The age limit for the upper caste candidates in 1980 WAS 30.

3. Which WAS his wife?

The girl who wore the red chudidhar WAS his wife.

4. Who WERE all our friends there in the function last week?
All of our friends WERE there in the function last week.

NOTE: We should use NOT with the auxiliary to make a sentence negative. The negative past tense auxiliaries: WAS NOT or WASN'T, WERE NOT or WEREN'T, HAD NOT or HADN'T are used to make a sentence negative in the past tense.

Example:

When I came your house yesterday, you WERE NOT there.

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