• Past simple tense : It is used to express an action that happened or completed in past, usually a very little time before speaking, or action which is just completed. Time of action is not specified in terms of long time ago or short ago but it make a sense that the action has done a little time ago. For example, a person says, “I watched a movie”, it means the speaker of this sentence watched a movie a little time ago or little time ago in the same day.

Rules: 2nd form of verb (past simple) is used as main verb in the positive sentences and base form is used in negative and interrogative sentences.

• Positive Sentence

• Subject + main verb (past simple) + object
• Subject + 2nd form of verb (past simple) + object

Examples :
I killed a snake
He ate a mango.

• Negative sentences :

• Subject + (auxiliary verb + not) main verb (base form) + object
• Subject + did not + 1st form of verb or base form + object

Examples:
I did not kill a snake
He did not eat a mango

In negative sentence “did not” is written and the 1st form of verb (base verb) is used instead of using 2nd form (or past simple verb).

• Past Continuous tense: It is used to express a continued or ongoing action in past, an ongoing action which occurred in past and completed at some point in past. It expresses an ongoing nature of an action in past. For example, “he was laughing.” This sentence shows ongoing action (laughing) of a person which occurred in past. Past continuous tense is also called past progressive.

Rules: Auxiliary verb “was or were” is used in sentence. 1st form of verb or base verb + ing (present participle) is used as main verb in sentence.

• Positive sentences :

Subject + auxiliary verb + Main Verb (present participle) + objectSubject + was/were + (1st form of verb or base verb +ing) +object

Examples:
She was crying yesterday.
They were climbing on a hill.

If the subject is “he, she, It, I, singular or proper noun” then auxiliary verb “was” is used. If subject is “you, we, they or plural” then auxiliary verb “were” is used.

• Negative sentences :

• Subject + auxiliary verb + NOT + Main verb (present participle) + object
• Subject + was/were + NOT + (1st form of verb or base verb +ing) +object

Rules for using auxiliary verb after subject are same as mentioned above.

Examples :
She was not crying yesterday.
They were not climbing on a hill.

• Interrogative sentences :

• Auxiliary verb + Subject + Main verb (present participle) + object
• Was/were + Subject + (1st form of verb or base verb +ing) +object

The interrogative sentence starts with the auxiliary verb. If the subject is “he, she, It, I, singular or proper noun” then the sentence starts with auxiliary verb “was”. If subject is “you, we, they or plural” then the sentence starts with auxiliary verb “were”.

Examples :
Was she crying yesterday?
Were they climbing on a hill?

• Interrogative sentences :

• Auxiliary verb + subject + main verb (base verb) + object
• Did + subject + 1st form of verb (or base verb) + object

Interrogative sentence starts with “did” and the 1st form of verb (base verb) is used instead of using 2nd form (or past simple verb).

• Past perfect tense: It is used to express an action which has occurred in past (usually, a long time ago) and action which has occurred in past before another action in past.

For example :

• I had lived in America. (The sense of time in this sentence refers to a completed action in past and especially a long time ago)
• The students had gone before the teacher came. (The first part of sentence “The student has gone” is sentence of past perfect tense, it says about an action which occurred before another action in past which is “the teacher came”. The second part “the teacher came” is sentence of past simple tense. So such a sentence which express an action in past before another action in past comprises two parts where the first part of sentence is past perfect tense)

Rules : Auxiliary verb “had” is used in sentence. 3rd form of verb (past participle) is used as main verb in sentence.

• Positive sentence

• Subject + auxiliary verb + main verb (past participle) + object
• Subject + had + 3rd form of verb or past participle + object

Examples:
He had taken the exam last year
A thief had stolen my watch.

• Negative sentence

• Subject + auxiliary verb + NOT + main verb (past participle) + object
• Subject + had + not + 3rd form of verb or past participle + object

Examples :
He had not taken the exam last year
A thief had not stolen my watch.

“Not” is written after auxiliary verb in negative sentence.

• Interrogative sentence :

• Auxiliary verb + subject + main verb (past participle) + object
• Had + subject + 3rd form of verb or past participle + object

• Interrogative sentence starts with auxiliary verb “had”

Examples :
Had he taken the exam last year
Had a thief stolen my watch?

• Past Perfect continuous tense: It is used to express a continued or ongoing action that started in past and continued until sometime in past.

Note: If there is not time reference or sense of time reference, then it is not Past perfect continuous tense because there is no hint about the time of action when it started in past or continued for some time period, so it seems just an ongoing action in past which resembles “past Continuous tense”. So the reference of time differentiates between Past perfect continuous tense and past continuous tense.

Rules : An auxiliary verb “had been” is used in sentence. 1st form of verb (base verb) +ing (present participle) is used as main verb in sentence. “Since” or “for” is used before the “time reference” in sentence. If the time reference is exactly known such as 1995, 4 O’clock then “since” is used before the time in sentence. If the time reference is not exactly known such as three hours, six years, four days, then “for” is used before the time in sentence. Time reference such as 3 hours or 5 days is not exactly known because we don’t know that about which three hours a day is told in sentence or about which 5 days in a month is told in sentence.

• Subject + Auxiliary verb + main verb (Present participle) + Object + Time reference
• Subject + had been + (1st form of verb or base verb + ing) + object + time reference

Examples :
I had been waiting for him for one hour.
She had been playing chess since 7 O’clock.

• Negative Sentence :

• Subject +”Not” between the Auxiliary verbs + main verb (present participle) + Object + Time reference
• Subject + had not been + (1st form of verb or base verb + ing) + object + time reference

Examples :
I had not been waiting for him for one hour.
She had not been playing chess since 7 O’clock.

To make negative sentence, the word “not” is added inside auxiliary verb, so it becomes “had not been”.

• Interrogative Sentence :

• Auxiliary verb+ Subject + Auxiliary verb + main verb (present participle) + object + time reference
• Had + Subject + been + (1st form of verb or base verb+ing) + object + time reference

Examples :
Had I been waiting for him for one hour?
Had she been playing chess 7 O’clock?

Interrogative sentence starts with auxiliary verb “had” and auxiliary verb “been” is used after subject in sentence.