PAST TENSE

Past tense is a grammatical tense that places an action or situation in the past of the current moment (in an absolute tense system), or prior to some specified time that may be in the speaker's past, present, or future (in a relative tense system).

1. Simple Past Tense is used to talk about actions that happened at a specific time in the past. You state when it happened using a time adverb.
The formula of Simple Past Tense :
(+ ) S + Verb 2 + O.
( - ) S + did not + Verb 1 + O.
(? )Did + S + Verb 1 + O.

Examples : 
(+ ) They came to my house the day before yesterday.
( - ) They did not come to my house the day before yesterday.
(? ) Did they come to my house the day before yesterday?

Past Continuous Tense is use to express action that was doing at the past or to indicate that a longer action in the past was interrupted.

The formula for Past Continuous Tense:

S + was/were + Verb₁ + ing + Object

The Object in here can be like: at 5 pm yesterday, at this time, when + S + Verb₂, while + S + was/were + Verb₁ + ing

Examples:

1. I was studying when she called

2. While I was studying, she called

3. He wasn’t at school at 3 pm yesterday

4. Who was sleeping at this time yesterday?

Past perfect tense is used to indicate that one action occurred before another action in the past. In other words, past perfect tense indicates the first of the two actions.

(+) Subject + had + verb3 + object + modifier

(-) Subject + had not + verb3 + object + modifier

(?) Had + subject + verb3 + object + modifier ?

Examples :

• You had studied English before you moved to New York.
• Had you studied English before you moved to New York?
• You had not studied English before you moved to New York.